diff --git a/Parameters_October22.md b/Parameters_October22.md new file mode 100644 index 0000000..4fd4dfe --- /dev/null +++ b/Parameters_October22.md @@ -0,0 +1,6745 @@ +### Parameter values for YouTube simulations ### + +Created by **Nils Berglund** and optimized by **Marco Mancini** + +C code for videos on YouTube Channel https://www.youtube.com/c/NilsBerglund + +Below are parameter values used for different simulations, as well as initial conditions used in +function animation. Some simulations use variants of the published code. The list is going to be +updated gradually. + + +### 31 October 22 - Phase space representation of a Penrose room of varying length ### + +**Program:** `billiard_phase_space.c` + +**In function `animation()`:** `lyap_exponents[i] = draw_phase_portrait(20, 20, 200, 20, 0.1);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define XPHASEMAX 0.0 /* max x coordinate of phase portrait */ + +#define PIXELIZE 0 /* set to 1 to pixelize phase portrait (beta) */ +#define NGRID 200 /* size of grid to draw orbits with positive Lyapunov exponent */ + +#define SYMMETRIZE_S 1 /* set to 1 to symmetrize orbits wrt s */ + +#define SCALING_FACTOR 1.0 /* scaling factor of drawing, needed for flower billiards, otherwise set to 1.0 */ + +/* Choice of the billiard table, see global_particles.c */ + +#define B_DOMAIN 16 /* choice of domain shape */ + +#define CIRCLE_PATTERN 6 /* pattern of circles */ +#define POLYLINE_PATTERN 4 /* pattern of polyline */ + +#define ABSORBING_CIRCLES 1 /* set to 1 for circular scatterers to be absorbing */ + +#define NMAXCIRCLES 50000 /* total number of circles (must be at least NCX*NCY for square grid) */ +#define NMAXPOLY 50000 /* total number of sides of polygonal line */ +#define NCX 9 /* number of circles in x direction */ +#define NCY 20 /* number of circles in y direction */ +#define NPOISSON 500 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define NGOLDENSPIRAL 2000 /* max number of points for C_GOLDEN_SPIRAL arrandement */ +#define SDEPTH 2 /* Sierpinski gastket depth */ + +#define LAMBDAMIN 0.8 /* parameter controlling shape of domain */ +#define LAMBDA 1.8 /* parameter controlling shape of domain */ +#define MU 0.2 /* second parameter controlling shape of billiard */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NPOLY 4 /* number of sides of polygon */ +#define APOLY -1.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define DRAW_BILLIARD 1 /* set to 1 to draw billiard */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw additional construction lines for billiard */ +#define PERIODIC_BC 0 /* set to 1 to enforce periodic boundary conditions when drawing particles */ +#define PENROSE_RATIO 1.0 /* parameter controlling the shape of small ellipses in Penrose room */ + +#define RESAMPLE 0 /* set to 1 if particles should be added when dispersion too large */ +#define DEBUG 0 /* draw trajectories, for debugging purposes */ + +/* Simulation parameters */ + +#define NPART 1 /* number of particles */ +#define NPARTMAX 100000 /* maximal number of particles after resampling */ +#define TRAJ_LENGTH 10000 /* length of trajectory */ +#define LMAX 0.01 /* minimal segment length triggering resampling */ +#define DMIN 0.02 /* minimal distance to boundary for triggering resampling */ +#define CYCLE 1 /* set to 1 for closed curve (start in all directions) */ +#define SHOWTRAILS 0 /* set to 1 to keep trails of the particles */ +#define SHOWZOOM 0 /* set to 1 to show zoom on specific area */ +#define TEST_ACTIVE 1 /* set to 1 to test whether particle is in billiard */ +#define PRINT_TRAJECTORY_LENGTH 0 /* set to 1 to print length of trajectory 0 */ +#define PRINT_TRAJECTORY_PERIOD 0 /* set to 1 to print period of trajectory 0 */ +#define DRAW_LENGTHS_PLOT 0 /* set to 1 to plot trajectory lengths */ +#define LENGTHS_LOG_SCALE 1 /* set to 1 to use log scale for plot of lengths */ +#define MAX_ANGLE 90.0 /* range of angles of trajectory */ + +#define NSTEPS 2200 /* number of frames of movie */ +#define TIME 2500 /* time between movie frames, for fluidity of real-time simulation */ +#define DPHI 0.00001 /* integration step */ +#define NVID 150 /* number of iterations between images displayed on screen */ +#define SYMMETRIC_PARAMETER 1 /* set to 1 if parameters depend symmetrically on time */ + +/* Decreasing TIME accelerates the animation and the movie */ +/* For constant speed of movie, TIME*DPHI should be kept constant */ +/* However, increasing DPHI too much deterioriates quality of simulation */ +/* NVID tells how often a picture is drawn in the animation, increase it for faster anim */ +/* For a good quality movie, take for instance TIME = 400, DPHI = 0.00005, NVID = 100 */ + +/* Colors and other graphical parameters */ + +#define COLOR_PALETTE 11 /* Color palette, see list in global_pdes.c */ + +#define NCOLORS 64 /* number of colors */ +#define CFACTOR 3 /* color step */ +#define COLORSHIFT 0 /* hue of initial color */ +#define LYAP_PLOT_COLOR 200.0 /* color hue of Lyapunov exponent plot */ +#define RAINBOW_COLOR 0 /* set to 1 to use different colors for all particles */ +#define FLOWER_COLOR 0 /* set to 1 to adapt initial colors to flower billiard (tracks vs core) */ +#define NSEG 100 /* number of segments of boundary */ +#define LENGTH 0.03 /* length of velocity vectors */ +#define BILLIARD_WIDTH 2 /* width of billiard */ +#define PARTICLE_WIDTH 2 /* width of particles */ +#define FRONT_WIDTH 3 /* width of wave front */ + +#define BLACK 1 /* set to 1 for black background */ +#define COLOR_OUTSIDE 0 /* set to 1 for colored outside */ +#define OUTER_COLOR 270.0 /* color outside billiard */ +#define PAINT_INT 0 /* set to 1 to paint interior in other color (for polygon/Reuleaux) */ +#define PAINT_EXT 1 /* set to 1 to paint exterior */ + +#define PRINT_LAMBDA 1 /* set to 1 to print value of lambda */ +#define PRINT_MU 0 /* set to 1 to print value of mu */ +#define PRINT_PENROSE_RATIO 0 /* set to 1 to print value of the Penrose billiard ratio */ +#define PRINT_LYAPUNOV 1 /* set to 1 to print mean Lyapunov exponent */ +#define PLOT_LYAPUNOV 1 /* set to 1 to add plot of Lyapunov exponents */ +#define LOGSCALEX_LYAP 0 /* set to 1 to use log scale on parameter axis of Lyapunov exponents */ +#define LYAP_MAX 0.7 /* maximal Lyapunov exponent */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define END_FRAMES 100 /* number of frames at end of movie */ + +``` + + +### 30 October 22 - Quantum maze: Solved and not solved at the same time ### + +**Program:** `rde.c` + +**Initial condition in function `animation()`:** `init_coherent_state(-1.2, 0.35, 5.0, -2.0, 0.1, phi, xy_in);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 480 /* number of grid points on x axis */ +#define NY 250 /* number of grid points on y axis */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +/* Choice of simulated equation */ + +#define RDE_EQUATION 5 /* choice of reaction term, see list in global_3d.c */ +#define NFIELDS 2 /* number of fields in reaction-diffusion equation */ +#define NLAPLACIANS 2 /* number of fields for which to compute Laplacian */ + +#define ADD_POTENTIAL 0 /* set to 1 to add a potential (for Schrodinger equation) */ +#define ADD_MAGNETIC_FIELD 0 /* set to 1 to add a magnetic field (for Schrodinger equation) - then set POTENTIAL 1 */ +#define POTENTIAL 101 /* type of potential or vector potential, see list in global_3d.c */ + +#define ANTISYMMETRIZE_WAVE_FCT 0 /* set tot 1 to make wave function antisymmetric */ + +#define JULIA_SCALE 0.5 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 54 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 99 /* pattern of circles, see list in global_pdes.c */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 1.0 /* parameter controlling the dimensions of domain */ +#define MU 1.0 /* parameter controlling the dimensions of domain */ +#define NPOLY 5 /* number of sides of polygon */ +#define APOLY 2.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 7 /* depth of computation of Menger gasket */ +#define MRATIO 5 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 15 /* number of grid point for grid of disks */ +#define NGRIDY 20 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -1.65 +#define ISO_XSHIFT_RIGHT 0.4 +#define ISO_YSHIFT_LEFT -0.05 +#define ISO_YSHIFT_RIGHT -0.05 +#define ISO_SCALE 0.85 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard in sub_wave.c */ + +/* Physical patameters of wave equation */ + +#define DT 0.00000002 + +#define VISCOSITY 2.0 + +#define RPSA 0.75 /* parameter in Rock-Paper-Scissors-type interaction */ +#define RPSLZB 0.75 /* second parameter in Rock-Paper-Scissors-Lizard-Spock type interaction */ + +#define EPSILON 0.8 /* time scale separation */ +#define DELTA 0.1 /* time scale separation */ +#define FHNA 1.0 /* parameter in FHN equation */ +#define FHNC -0.01 /* parameter in FHN equation */ +#define K_HARMONIC 1.0 /* spring constant of harmonic potential */ +#define K_COULOMB 0.5 /* constant in Coulomb potential */ +#define BZQ 0.0008 /* parameter in BZ equation */ +#define BZF 1.2 /* parameter in BZ equation */ +#define B_FIELD 10.0 /* magnetic field */ +#define AB_RADIUS 0.2 /* radius of region with magnetic field for Aharonov-Bohm effect */ +#define K_EULER 50.0 /* constant in stream function integration of Euler equation */ + +#define SMOOTHEN_VORTICITY 1 /* set to 1 to smoothen vorticity field in Euler equation */ +#define SMOOTHEN_PERIOD 10 /* period between smoothenings */ +#define SMOOTH_FACTOR 0.015 /* factor by which to smoothen */ + +#define T_OUT 2.0 /* outside temperature */ +#define T_IN 0.0 /* inside temperature */ +#define SPEED 0.0 /* speed of drift to the right */ + +#define ADD_NOISE 0 /* set to 1 to add noise, set to 2 to add noise in right half */ +#define NOISE_INTENSITY 0.005 /* noise intensity */ +#define CHANGE_NOISE 1 /* set to 1 to increase noise intensity */ +#define NOISE_FACTOR 40.0 /* factor by which to increase noise intensity */ +#define NOISE_INITIAL_TIME 100 /* initial time during which noise remains constant */ + +#define CHANGE_VISCOSITY 0 /* set to 1 to change the viscosity in the course of the simulation */ +#define ADJUST_INTSTEP 0 /* set to 1 to decrease integration step when viscosity increases */ +#define VISCOSITY_INITIAL_TIME 10 /* initial time during which viscosity remains constant */ +#define VISCOSITY_FACTOR 100.0 /* factor by which to change viscosity */ +#define VISCOSITY_MAX 2.0 /* max value of viscosity beyond which NVID is increased and integration step is decrase, + for numerical stability */ + +#define CHANGE_RPSLZB 0 /* set to 1 to change second parameter in Rock-Paper-Scissors-Lizard-Spock equation */ +#define RPSLZB_CHANGE 0.75 /* factor by which to rpslzb parameter */ +#define RPSLZB_INITIAL_TIME 0 /* initial time during which rpslzb remains constant */ +#define RPSLZB_FINAL_TIME 500 /* final time during which rpslzb remains constant */ + + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 1 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 3000 /* number of frames of movie */ +#define NVID 480 /* number of iterations between images displayed on screen */ +#define ACCELERATION_FACTOR 1.0 /* factor by which to increase NVID in course of simulation */ +#define DT_ACCELERATION_FACTOR 1.0 /* factor by which to increase time step in course of simulation */ +#define MAX_DT 0.024 /* maximal value of integration step */ +#define NSEG 100 /* number of segments of boundary */ +#define BOUNDARY_WIDTH 5 /* width of billiard boundary */ + +#define PAUSE 100 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 2 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define INITIAL_TIME 0 /* initial still time */ +#define MID_FRAMES 50 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 50 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Visualisation */ + +#define PLOT_3D 1 /* controls whether plot is 2D or 3D */ + +#define ROTATE_VIEW 0 /* set to 1 to rotate position of observer */ +#define ROTATE_ANGLE 360.0 /* total angle of rotation during simulation */ + +/* Plot type - color scheme */ + +#define CPLOT 30 +#define CPLOT_B 31 + +/* Plot type - height of 3D plot */ + +#define ZPLOT 30 /* z coordinate in 3D plot */ +#define ZPLOT_B 30 /* z coordinate in second 3D plot */ + +#define AMPLITUDE_HIGH_RES 1 /* set to 1 to increase resolution of P_3D_AMPLITUDE plot */ +#define SHADE_3D 1 /* set to 1 to change luminosity according to normal vector */ +#define NON_DIRICHLET_BC 0 /* set to 1 to draw only facets in domain, if field is not zero on boundary */ +#define WRAP_ANGLE 1 /* experimental: wrap angle to [0, 2Pi) for interpolation in angle schemes */ +#define FADE_IN_OBSTACLE 0 /* set to 1 to fade color inside obstacles */ +#define DRAW_OUTSIDE_GRAY 0 /* experimental - draw outside of billiard in gray */ +#define ADD_POTENTIAL_TO_Z 1 /* set to 1 to add the external potential to z-coordinate of plot */ +#define ADD_POT_CONSTANT 0.5 /* constant in front of added potential */ + +#define PLOT_SCALE_ENERGY 0.05 /* vertical scaling in energy plot */ + +#define PRINT_TIME 0 /* set to 1 to print running time */ +#define PRINT_VISCOSITY 0 /* set to 1 to print viscosity */ +#define PRINT_RPSLZB 0 /* set to 1 to print rpslzb parameter */ +#define PRINT_PROBABILITIES 0 /* set to 1 to print probabilities (for Ehrenfest urn configuration) */ +#define PRINT_NOISE 0 /* set to 1 to print noise intensity */ + +#define DRAW_FIELD_LINES 0 /* set to 1 to draw field lines */ +#define FIELD_LINE_WIDTH 1 /* width of field lines */ +#define N_FIELD_LINES 120 /* number of field lines */ +#define FIELD_LINE_FACTOR 120 /* factor controlling precision when computing origin of field lines */ +#define DRAW_BILLIARD 1 /* set to 1 to draw boundary */ +#define DRAW_BILLIARD_FRONT 1 /* set to 1 to draw boundary */ +#define FILL_BILLIARD_COMPLEMENT 1 /* set to 1 to fill complement of billiard (for certain shapes only) */ + +/* 3D representation */ + +#define REPRESENTATION_3D 1 /* choice of 3D representation */ + +#define REP_AXO_3D 0 /* linear projection (axonometry) */ +#define REP_PROJ_3D 1 /* projection on plane orthogonal to observer line of sight */ + +/* Color schemes, see list in global_pdes.c */ + +#define COLOR_PALETTE 11 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 0 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* black background */ + +#define COLOR_SCHEME 3 /* choice of color scheme */ + +#define COLOR_PHASE_SHIFT 0.0 /* phase shift of color scheme, in units of Pi */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define VSCALE_AMPLITUDE 30.0 /* additional scaling factor for color scheme P_3D_AMPLITUDE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define CURL_SCALE 0.000015 /* scaling factor for curl representation */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ +#define SLOPE_SCHROD_LUM 50.0 /* sensitivity of luminosity on module, for color scheme Z_ARGUMENT */ +#define MIN_SCHROD_LUM 0.2 /* minimal luminosity in color scheme Z_ARGUMENT*/ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 359.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -359.0 /* amplitude of variation of hue for color scheme C_HUE */ +#define E_SCALE 100.0 /* scaling factor for energy representation */ +#define LOG_SCALE 0.75 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 + +#define NXMAZE 7 /* width of maze */ +#define NYMAZE 7 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 24 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 3.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 2.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +/* only for compatibility with wave_common.c */ +#define TWOSPEEDS 0 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OMEGA 0.005 /* frequency of periodic excitation */ +#define COURANT 0.08 /* Courant number */ +#define COURANTB 0.03 /* Courant number in medium B */ +#define INITIAL_AMP 0.5 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.1 /* wavelength of initial condition */ +#define VSCALE_ENERGY 200.0 /* additional scaling factor for color scheme P_3D_ENERGY */ +#define PHASE_FACTOR 20.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define OSCILLATION_SCHEDULE 0 /* oscillation schedule, see list in global_pdes.c */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.2 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ +/* end of constants added only for compatibility with wave_common.c */ + + +double u_3d[2] = {0.75, -0.45}; /* projections of basis vectors for REP_AXO_3D representation */ +double v_3d[2] = {-0.75, -0.45}; +double w_3d[2] = {0.0, 0.015}; +double light[3] = {0.816496581, -0.40824829, 0.40824829}; /* vector of "light" direction for P_3D_ANGLE color scheme */ +double observer[3] = {8.0, 8.0, 8.0}; /* location of observer for REP_PROJ_3D representation */ +int reset_view = 0; /* switch to reset 3D view parameters (for option ROTATE_VIEW) */ + +#define Z_SCALING_FACTOR 1.25 /* overall scaling factor of z axis for REP_PROJ_3D representation */ +#define XY_SCALING_FACTOR 1.8 /* overall scaling factor for on-screen (x,y) coordinates after projection */ +#define ZMAX_FACTOR 1.0 /* max value of z coordinate for REP_PROJ_3D representation */ +#define XSHIFT_3D -0.1 /* overall x shift for REP_PROJ_3D representation */ +#define YSHIFT_3D 0.0 /* overall y shift for REP_PROJ_3D representation */ +#define BORDER_PADDING 2 /* distance from boundary at which to plot points, to avoid boundary effects due to gradient */ + +/* For debugging purposes only */ +#define FLOOR 1 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ +#define TEST_GRADIENT 0 /* print norm squared of gradient */ + +``` + +### 29 October 22 - A shear flow with 4 layers ### + +**Program:** `rde.c` + +**Initial condition in function `animation()`:** `init_shear_flow(0.1, 0.25, 2, 2, phi, xy_in);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ + +#define NX 960 /* number of grid points on x axis */ +#define NY 500 /* number of grid points on y axis */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +/* Choice of simulated equation */ + +#define RDE_EQUATION 6 /* choice of reaction term, see list in global_3d.c */ +#define NFIELDS 2 /* number of fields in reaction-diffusion equation */ +#define NLAPLACIANS 1 /* number of fields for which to compute Laplacian */ + +#define ADD_POTENTIAL 0 /* set to 1 to add a potential (for Schrodinger equation) */ +#define ADD_MAGNETIC_FIELD 0 /* set to 1 to add a magnetic field (for Schrodinger equation) - then set POTENTIAL 1 */ +#define POTENTIAL 101 /* type of potential or vector potential, see list in global_3d.c */ + +#define ANTISYMMETRIZE_WAVE_FCT 0 /* set tot 1 to make wave function antisymmetric */ + +#define JULIA_SCALE 0.5 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 999 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 99 /* pattern of circles, see list in global_pdes.c */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 1.0 /* parameter controlling the dimensions of domain */ +#define MU 1.0 /* parameter controlling the dimensions of domain */ +#define NPOLY 5 /* number of sides of polygon */ +#define APOLY 2.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 7 /* depth of computation of Menger gasket */ +#define MRATIO 5 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 15 /* number of grid point for grid of disks */ +#define NGRIDY 20 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -1.65 +#define ISO_XSHIFT_RIGHT 0.4 +#define ISO_YSHIFT_LEFT -0.05 +#define ISO_YSHIFT_RIGHT -0.05 +#define ISO_SCALE 0.85 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard in sub_wave.c */ + +/* Physical patameters of wave equation */ + +#define DT 0.0000012 + +#define VISCOSITY 2.0 + +#define RPSA 0.75 /* parameter in Rock-Paper-Scissors-type interaction */ +#define RPSLZB 0.75 /* second parameter in Rock-Paper-Scissors-Lizard-Spock type interaction */ + +#define EPSILON 0.8 /* time scale separation */ +#define DELTA 0.1 /* time scale separation */ +#define FHNA 1.0 /* parameter in FHN equation */ +#define FHNC -0.01 /* parameter in FHN equation */ +#define K_HARMONIC 1.0 /* spring constant of harmonic potential */ +#define K_COULOMB 0.5 /* constant in Coulomb potential */ +#define BZQ 0.0008 /* parameter in BZ equation */ +#define BZF 1.2 /* parameter in BZ equation */ +#define B_FIELD 10.0 /* magnetic field */ +#define AB_RADIUS 0.2 /* radius of region with magnetic field for Aharonov-Bohm effect */ +#define K_EULER 50.0 /* constant in stream function integration of Euler equation */ + +#define SMOOTHEN_VORTICITY 1 /* set to 1 to smoothen vorticity field in Euler equation */ +#define SMOOTHEN_PERIOD 10 /* period between smoothenings */ +#define SMOOTH_FACTOR 0.014 /* factor by which to smoothen */ + +#define T_OUT 2.0 /* outside temperature */ +#define T_IN 0.0 /* inside temperature */ +#define SPEED 0.0 /* speed of drift to the right */ + +#define ADD_NOISE 0 /* set to 1 to add noise, set to 2 to add noise in right half */ +#define NOISE_INTENSITY 0.005 /* noise intensity */ +#define CHANGE_NOISE 1 /* set to 1 to increase noise intensity */ +#define NOISE_FACTOR 40.0 /* factor by which to increase noise intensity */ +#define NOISE_INITIAL_TIME 100 /* initial time during which noise remains constant */ + +#define CHANGE_VISCOSITY 0 /* set to 1 to change the viscosity in the course of the simulation */ +#define ADJUST_INTSTEP 0 /* set to 1 to decrease integration step when viscosity increases */ +#define VISCOSITY_INITIAL_TIME 10 /* initial time during which viscosity remains constant */ +#define VISCOSITY_FACTOR 100.0 /* factor by which to change viscosity */ +#define VISCOSITY_MAX 2.0 /* max value of viscosity beyond which NVID is increased and integration step is decrase, + for numerical stability */ + +#define CHANGE_RPSLZB 0 /* set to 1 to change second parameter in Rock-Paper-Scissors-Lizard-Spock equation */ +#define RPSLZB_CHANGE 0.75 /* factor by which to rpslzb parameter */ +#define RPSLZB_INITIAL_TIME 0 /* initial time during which rpslzb remains constant */ +#define RPSLZB_FINAL_TIME 500 /* final time during which rpslzb remains constant */ + + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 1 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 2650 /* number of frames of movie */ +#define NVID 100 /* number of iterations between images displayed on screen */ +#define ACCELERATION_FACTOR 1.0 /* factor by which to increase NVID in course of simulation */ +#define DT_ACCELERATION_FACTOR 1.0 /* factor by which to increase time step in course of simulation */ +#define MAX_DT 0.024 /* maximal value of integration step */ +#define NSEG 100 /* number of segments of boundary */ +#define BOUNDARY_WIDTH 5 /* width of billiard boundary */ + +#define PAUSE 100 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 2 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define INITIAL_TIME 0 /* initial still time */ +#define MID_FRAMES 50 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 50 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Visualisation */ + +#define PLOT_3D 0 /* controls whether plot is 2D or 3D */ + +#define ROTATE_VIEW 0 /* set to 1 to rotate position of observer */ +#define ROTATE_ANGLE 360.0 /* total angle of rotation during simulation */ + +/* Plot type - color scheme */ + +#define CPLOT 52 +#define CPLOT_B 51 + +/* Plot type - height of 3D plot */ + +#define ZPLOT 52 /* z coordinate in 3D plot */ +#define ZPLOT_B 51 /* z coordinate in second 3D plot */ + +#define AMPLITUDE_HIGH_RES 1 /* set to 1 to increase resolution of P_3D_AMPLITUDE plot */ +#define SHADE_3D 1 /* set to 1 to change luminosity according to normal vector */ +#define NON_DIRICHLET_BC 0 /* set to 1 to draw only facets in domain, if field is not zero on boundary */ +#define WRAP_ANGLE 1 /* experimental: wrap angle to [0, 2Pi) for interpolation in angle schemes */ +#define FADE_IN_OBSTACLE 0 /* set to 1 to fade color inside obstacles */ +#define DRAW_OUTSIDE_GRAY 0 /* experimental - draw outside of billiard in gray */ +#define ADD_POTENTIAL_TO_Z 1 /* set to 1 to add the external potential to z-coordinate of plot */ +#define ADD_POT_CONSTANT 0.5 /* constant in front of added potential */ + +#define PLOT_SCALE_ENERGY 0.05 /* vertical scaling in energy plot */ + +#define PRINT_TIME 0 /* set to 1 to print running time */ +#define PRINT_VISCOSITY 0 /* set to 1 to print viscosity */ +#define PRINT_RPSLZB 0 /* set to 1 to print rpslzb parameter */ +#define PRINT_PROBABILITIES 0 /* set to 1 to print probabilities (for Ehrenfest urn configuration) */ +#define PRINT_NOISE 0 /* set to 1 to print noise intensity */ + +#define DRAW_FIELD_LINES 0 /* set to 1 to draw field lines */ +#define FIELD_LINE_WIDTH 1 /* width of field lines */ +#define N_FIELD_LINES 120 /* number of field lines */ +#define FIELD_LINE_FACTOR 120 /* factor controlling precision when computing origin of field lines */ +#define DRAW_BILLIARD 1 /* set to 1 to draw boundary */ +#define DRAW_BILLIARD_FRONT 1 /* set to 1 to draw boundary */ +#define FILL_BILLIARD_COMPLEMENT 1 /* set to 1 to fill complement of billiard (for certain shapes only) */ + +/* 3D representation */ + +#define REPRESENTATION_3D 1 /* choice of 3D representation */ + +#define REP_AXO_3D 0 /* linear projection (axonometry) */ +#define REP_PROJ_3D 1 /* projection on plane orthogonal to observer line of sight */ + +/* Color schemes, see list in global_pdes.c */ + +#define COLOR_PALETTE 18 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 12 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* black background */ + +#define COLOR_SCHEME 3 /* choice of color scheme */ + +#define COLOR_PHASE_SHIFT 0.0 /* phase shift of color scheme, in units of Pi */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define VSCALE_AMPLITUDE 1.0 /* additional scaling factor for color scheme P_3D_AMPLITUDE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define CURL_SCALE 0.000015 /* scaling factor for curl representation */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ +#define SLOPE_SCHROD_LUM 50.0 /* sensitivity of luminosity on module, for color scheme Z_ARGUMENT */ +#define MIN_SCHROD_LUM 0.2 /* minimal luminosity in color scheme Z_ARGUMENT*/ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 359.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -359.0 /* amplitude of variation of hue for color scheme C_HUE */ +#define E_SCALE 100.0 /* scaling factor for energy representation */ +#define LOG_SCALE 0.75 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 3.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 2.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +/* only for compatibility with wave_common.c */ +#define TWOSPEEDS 0 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OMEGA 0.005 /* frequency of periodic excitation */ +#define COURANT 0.08 /* Courant number */ +#define COURANTB 0.03 /* Courant number in medium B */ +#define INITIAL_AMP 0.5 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.1 /* wavelength of initial condition */ +#define VSCALE_ENERGY 200.0 /* additional scaling factor for color scheme P_3D_ENERGY */ +#define PHASE_FACTOR 20.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define OSCILLATION_SCHEDULE 0 /* oscillation schedule, see list in global_pdes.c */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.2 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ +#define NXMAZE 8 /* width of maze */ +#define NYMAZE 8 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 58 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ +/* end of constants added only for compatibility with wave_common.c */ + + +double u_3d[2] = {0.75, -0.45}; /* projections of basis vectors for REP_AXO_3D representation */ +double v_3d[2] = {-0.75, -0.45}; +double w_3d[2] = {0.0, 0.015}; +double light[3] = {0.816496581, -0.40824829, 0.40824829}; /* vector of "light" direction for P_3D_ANGLE color scheme */ +double observer[3] = {8.0, 8.0, 8.0}; /* location of observer for REP_PROJ_3D representation */ +int reset_view = 0; /* switch to reset 3D view parameters (for option ROTATE_VIEW) */ + +#define Z_SCALING_FACTOR 1.0 /* overall scaling factor of z axis for REP_PROJ_3D representation */ +#define XY_SCALING_FACTOR 1.8 /* overall scaling factor for on-screen (x,y) coordinates after projection */ +#define ZMAX_FACTOR 1.0 /* max value of z coordinate for REP_PROJ_3D representation */ +#define XSHIFT_3D -0.1 /* overall x shift for REP_PROJ_3D representation */ +#define YSHIFT_3D 0.0 /* overall y shift for REP_PROJ_3D representation */ +#define BORDER_PADDING 2 /* distance from boundary at which to plot points, to avoid boundary effects due to gradient */ + +/* For debugging purposes only */ +#define FLOOR 1 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ +#define TEST_GRADIENT 0 /* print norm squared of gradient */ + +``` + +### 28 October 22 - Bloopers 3: Rockets messing with the thermostat ### + +**Program:** `lennardjones.c` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 0 /* set to 1 to produce movies for wave height and energy simultaneously */ + +#define TIME_LAPSE 1 /* set to 1 to add a time-lapse movie at the end */ + /* so far incompatible with double movie */ +#define TIME_LAPSE_FACTOR 3 /* factor of time-lapse movie */ +#define TIME_LAPSE_FIRST 1 /* set to 1 to show time-lapse version first */ + +/* General geometrical parameters */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -3.3 +#define XMAX 4.7 /* x interval */ +#define YMIN -2.25 +#define YMAX 2.25 /* y interval for 9/16 aspect ratio */ + +#define INITXMIN -2.0 +#define INITXMAX 2.0 /* x interval for initial condition */ +#define INITYMIN -1.7 +#define INITYMAX 0.5 /* y interval for initial condition */ + +#define BCXMIN -5.1 +#define BCXMAX 6.1 /* x interval for boundary condition */ +#define BCYMIN -6.5 +#define BCYMAX 44.0 /* y interval for boundary condition */ + +#define OBSXMIN -2.0 +#define OBSXMAX 2.0 /* x interval for motion of obstacle */ + +#define CIRCLE_PATTERN 8 /* pattern of circles, see list in global_ljones.c */ + +#define ADD_FIXED_OBSTACLES 0 /* set to 1 do add fixed circular obstacles */ +#define OBSTACLE_PATTERN 3 /* pattern of obstacles, see list in global_ljones.c */ + +#define ADD_FIXED_SEGMENTS 1 /* set to 1 to add fixed segments as obstacles */ +#define SEGMENT_PATTERN 102 /* pattern of repelling segments, see list in global_ljones.c */ +#define ROCKET_SHAPE 1 /* shape of rocket combustion chamber, see list in global_ljones.c */ +#define ROCKET_SHAPE_B 1 /* shape of second rocket */ +#define NOZZLE_SHAPE 1 /* shape of nozzle, see list in global_ljones.c */ +#define NOZZLE_SHAPE_B 99 /* shape of nozzle for second rocket, see list in global_ljones.c */ + +#define TWO_TYPES 0 /* set to 1 to have two types of particles */ +#define TPYE_PROPORTION 0.5 /* proportion of particles of first type */ +#define SYMMETRIZE_FORCE 1 /* set to 1 to symmetrize two-particle interaction, only needed if particles are not all the same */ +#define CENTER_PX 0 /* set to 1 to center horizontal momentum */ +#define CENTER_PY 0 /* set to 1 to center vertical momentum */ +#define CENTER_PANGLE 0 /* set to 1 to center angular momentum */ + +#define INTERACTION 1 /* particle interaction, see list in global_ljones.c */ +#define INTERACTION_B 1 /* particle interaction for second type of particle, see list in global_ljones.c */ +#define SPIN_INTER_FREQUENCY 5.0 /* angular frequency of spin-spin interaction */ +#define SPIN_INTER_FREQUENCY_B 2.0 /* angular frequency of spin-spin interaction for second particle type */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 100 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define PDISC_DISTANCE 2.5 /* minimal distance in Poisson disc process, controls density of particles */ +#define PDISC_CANDIDATES 100 /* number of candidates in construction of Poisson disc process */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.8 /* parameter controlling the dimensions of domain */ +#define MU 0.009 /* parameter controlling radius of particles */ +#define MU_B 0.018 /* parameter controlling radius of particles of second type */ +#define NPOLY 25 /* number of sides of polygon */ +#define APOLY 0.666666666 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 4 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 90 /* number of grid point for grid of disks */ +#define NGRIDY 100 /* number of grid point for grid of disks */ +#define EHRENFEST_RADIUS 0.9 /* radius of container for Ehrenfest urn configuration */ +#define EHRENFEST_WIDTH 0.035 /* width of tube for Ehrenfest urn configuration */ +#define TWO_CIRCLES_RADIUS_RATIO 0.8 /* ratio of radii for S_TWO_CIRCLES_EXT segment configuration */ +#define DAM_WIDTH 0.05 /* width of dam for S_DAM segment configuration */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 2000 /* number of frames of movie */ +#define NVID 100 /* number of iterations between images displayed on screen */ +#define NSEG 250 /* number of segments of boundary */ +#define INITIAL_TIME 10 /* time after which to start saving frames */ +#define OBSTACLE_INITIAL_TIME 200 /* time after which to start moving obstacle */ +#define BOUNDARY_WIDTH 1 /* width of particle boundary */ +#define LINK_WIDTH 2 /* width of links between particles */ +#define CONTAINER_WIDTH 4 /* width of container boundary */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ + +/* Boundary conditions, see list in global_ljones.c */ + +#define BOUNDARY_COND 20 + +/* Plot type, see list in global_ljones.c */ + +#define PLOT 0 +#define PLOT_B 8 /* plot type for second movie */ + +#define DRAW_BONDS 0 /* set to 1 to draw bonds between neighbours */ +#define COLOR_BONDS 1 /* set to 1 to color bonds according to length */ +#define FILL_TRIANGLES 1 /* set to 1 to fill triangles between neighbours */ +#define COLOR_SEG_GROUPS 1 /* set to 1 to collor segment groups differently */ + +/* Color schemes */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_ljones.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_ljones.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 0.5 /* sensitivity of color on wave amplitude */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 220.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -50.0 /* amplitude of variation of hue for color scheme C_HUE */ + +/* particle properties */ + +#define ENERGY_HUE_MIN 330.0 /* color of original particle */ +#define ENERGY_HUE_MAX 50.0 /* color of saturated particle */ +#define PARTICLE_HUE_MIN 359.0 /* color of original particle */ +#define PARTICLE_HUE_MAX 0.0 /* color of saturated particle */ +#define PARTICLE_EMAX 2.0e2 /* energy of particle with hottest color */ +#define HUE_TYPE0 70.0 /* hue of particles of type 0 */ +#define HUE_TYPE1 280.0 /* hue of particles of type 1 */ +#define HUE_TYPE2 .0 /* hue of particles of type 2 */ +#define HUE_TYPE3 210.0 /* hue of particles of type 3 */ + +#define RANDOM_RADIUS 0 /* set to 1 for random circle radius */ +#define DT_PARTICLE 3.0e-6 /* time step for particle displacement */ +#define KREPEL 12.0 /* constant in repelling force between particles */ +#define EQUILIBRIUM_DIST 4.5 /* Lennard-Jones equilibrium distance */ +#define EQUILIBRIUM_DIST_B 3.5 /* Lennard-Jones equilibrium distance for second type of particle */ +#define REPEL_RADIUS 20.0 /* radius in which repelling force acts (in units of particle radius) */ +#define DAMPING 5.0 /* damping coefficient of particles */ +#define PARTICLE_MASS 1.0 /* mass of particle of radius MU */ +#define PARTICLE_MASS_B 1.0 /* mass of particle of radius MU */ +#define PARTICLE_INERTIA_MOMENT 0.2 /* moment of inertia of particle */ +#define PARTICLE_INERTIA_MOMENT_B 0.02 /* moment of inertia of second type of particle */ +#define V_INITIAL 0.0 /* initial velocity range */ +#define OMEGA_INITIAL 10.0 /* initial angular velocity range */ + +#define THERMOSTAT 1 /* set to 1 to switch on thermostat */ +#define VARY_THERMOSTAT 0 /* set to 1 for time-dependent thermostat schedule */ +#define SIGMA 5.0 /* noise intensity in thermostat */ +#define BETA 0.02 /* initial inverse temperature */ +#define MU_XI 0.01 /* friction constant in thermostat */ +#define KSPRING_BOUNDARY 1.0e7 /* confining harmonic potential outside simulation region */ +#define KSPRING_OBSTACLE 1.0e11 /* harmonic potential of obstacles */ +#define NBH_DIST_FACTOR 7.5 /* radius in which to count neighbours */ +#define GRAVITY 15.0 /* gravity acting on all particles */ +#define GRAVITY_X 0.0 /* horizontal gravity acting on all particles */ +#define INCREASE_GRAVITY 0 /* set to 1 to increase gravity during the simulation */ +#define GRAVITY_SCHEDULE 2 /* type of gravity schedule, see list in global_ljones.c */ +#define GRAVITY_FACTOR 100.0 /* factor by which to increase gravity */ +#define GRAVITY_INITIAL_TIME 200 /* time at start of simulation with constant gravity */ +#define GRAVITY_RESTORE_TIME 700 /* time at end of simulation with gravity restored to initial value */ + +#define ROTATION 0 /* set to 1 to include rotation of particles */ +#define COUPLE_ANGLE_TO_THERMOSTAT 0 /* set to 1 to couple angular degrees of freedom to thermostat */ +#define DIMENSION_FACTOR 1.0 /* scaling factor taking into account number of degrees of freedom */ +#define KTORQUE 100.0 /* force constant in angular dynamics */ +#define KTORQUE_B 10.0 /* force constant in angular dynamics */ +#define KTORQUE_DIFF 150.0 /* force constant in angular dynamics for different particles */ +#define DRAW_SPIN 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_SPIN_B 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_CROSS 1 /* set to 1 to draw cross on particles of second type */ +#define SPIN_RANGE 7.0 /* range of spin-spin interaction */ +#define SPIN_RANGE_B 5.0 /* range of spin-spin interaction for second type of particle */ +#define QUADRUPOLE_RATIO 0.6 /* anisotropy in quadrupole potential */ + +#define INCREASE_BETA 1 /* set to 1 to increase BETA during simulation */ +#define BETA_FACTOR 0.025 /* factor by which to change BETA during simulation */ +#define N_TOSCILLATIONS 1.5 /* number of temperature oscillations in BETA schedule */ +#define NO_OSCILLATION 1 /* set to 1 to have exponential BETA change only */ +#define MIDDLE_CONSTANT_PHASE 900 /* final phase in which temperature is constant */ +#define FINAL_DECREASE_PHASE 900 /* final phase in which temperature decreases */ +#define FINAL_CONSTANT_PHASE -1 /* final phase in which temperature is constant */ + +#define DECREASE_CONTAINER_SIZE 0 /* set to 1 to decrease size of container */ +#define SYMMETRIC_DECREASE 0 /* set tp 1 to decrease container symmetrically */ +#define COMPRESSION_RATIO 0.3 /* final size of container */ +#define RESTORE_CONTAINER_SIZE 1 /* set to 1 to restore container to initial size at end of simulation */ +#define RESTORE_TIME 700 /* time before end of sim at which to restore size */ + +#define MOVE_OBSTACLE 0 /* set to 1 to have a moving obstacle */ +#define CENTER_VIEW_ON_OBSTACLE 0 /* set to 1 to center display on moving obstacle */ +#define RESAMPLE_Y 0 /* set to 1 to resample y coordinate of moved particles (for shock waves) */ +#define NTRIALS 2000 /* number of trials when resampling */ +#define OBSTACLE_RADIUS 0.12 /* radius of obstacle for circle boundary conditions */ +#define FUNNEL_WIDTH 0.25 /* funnel width for funnel boundary conditions */ +#define OBSTACLE_XMIN 0.0 /* initial position of obstacle */ +#define OBSTACLE_XMAX 3.0 /* final position of obstacle */ +#define RECORD_PRESSURES 0 /* set to 1 to record pressures on obstacle */ +#define N_PRESSURES 100 /* number of intervals to record pressure */ +#define N_P_AVERAGE 100 /* size of pressure averaging window */ +#define N_T_AVERAGE 50 /* size of temperature averaging window */ +#define MAX_PRESSURE 3.0e10 /* pressure shown in "hottest" color */ +#define PARTIAL_THERMO_COUPLING 0 /* set to 1 to couple only particles to the right of obstacle to thermostat */ +#define PARTIAL_THERMO_REGION 1 /* region for partial thermostat coupling (see list in global_ljones.c) */ +#define PARTIAL_THERMO_SHIFT 0.2 /* distance from obstacle at the right of which particles are coupled to thermostat */ +#define PARTIAL_THERMO_WIDTH 0.5 /* vertical size of partial thermostat coupling */ +#define PARTIAL_THERMO_HEIGHT 0.2 /* vertical size of partial thermostat coupling */ + +#define INCREASE_KREPEL 0 /* set to 1 to increase KREPEL during simulation */ +#define KREPEL_FACTOR 1000.0 /* factor by which to change KREPEL during simulation */ + +#define PART_AT_BOTTOM 0 /* set to 1 to include "seed" particles at bottom */ +#define MASS_PART_BOTTOM 10000.0 /* mass of particles at bottom */ +#define NPART_BOTTOM 100 /* number of particles at the bottom */ + +#define ADD_PARTICLES 0 /* set to 1 to add particles */ +#define ADD_TIME 0 /* time at which to add first particle */ +#define ADD_PERIOD 10000 /* time interval between adding further particles */ +#define FINAL_NOADD_PERIOD 200 /* final period where no particles are added */ +#define SAFETY_FACTOR 2.0 /* no particles are added at distance less than MU*SAFETY_FACTOR of other particles */ + +#define TRACER_PARTICLE 0 /* set to 1 to have a tracer particle */ +#define N_TRACER_PARTICLES 3 /* number of tracer particles */ +#define TRAJECTORY_LENGTH 8000 /* length of recorded trajectory */ +#define TRACER_PARTICLE_MASS 4.0 /* relative mass of tracer particle */ +#define TRAJECTORY_WIDTH 3 /* width of tracer particle trajectory */ + +#define ROTATE_BOUNDARY 0 /* set to 1 to rotate the repelling segments */ +#define SMOOTH_ROTATION 1 /* set to 1 to update segments at each time step (rather than at each movie frame) */ +#define PERIOD_ROTATE_BOUNDARY 1000 /* period of rotating boundary */ +#define ROTATE_INITIAL_TIME 0 /* initial time without rotation */ +#define ROTATE_FINAL_TIME 100 /* final time without rotation */ +#define ROTATE_CHANGE_TIME 0.33 /* relative duration of acceleration/deceleration phases */ +#define OMEGAMAX 100.0 /* maximal rotation speed */ +#define PRINT_OMEGA 0 /* set to 1 to print angular speed */ +#define PRINT_PARTICLE_SPEEDS 0 /* set to 1 to print average speeds/momenta of particles */ +#define PRINT_SEGMENTS_SPEEDS 1 /* set to 1 to print velocity of moving segments */ + +#define MOVE_BOUNDARY 0 /* set to 1 to move repelling segments, due to force from particles */ +#define SEGMENTS_MASS 40.0 /* mass of collection of segments */ +#define DEACTIVATE_SEGMENT 1 /* set to 1 to deactivate last segment after a certain time */ +#define SEGMENT_DEACTIVATION_TIME 200 /* time at which to deactivate last segment */ +#define RELEASE_ROCKET_AT_DEACTIVATION 1 /* set to 1 to limit segments velocity before segment release */ +#define SEGMENTS_X0 1.5 /* initial position of segments */ +#define SEGMENTS_Y0 0.0 /* initial position of segments */ +#define SEGMENTS_VX0 0.0 /* initial velocity of segments */ +#define SEGMENTS_VY0 0.0 /* initial velocity of segments */ +#define DAMP_SEGS_AT_NEGATIVE_Y 0 /* set to 1 to dampen segments when y coordinate is negative */ + +#define MOVE_SEGMENT_GROUPS 1 /* set to 1 to group segments into moving units */ +#define SEGMENT_GROUP_MASS 1000.0 /* mass of segment group */ +#define SEGMENT_GROUP_I 35.0 /* moment of inertia of segment group */ +#define SEGMENT_GROUP_DAMPING 0.0 /* damping of segment groups */ +#define GROUP_REPULSION 1 /* set to 1 for groups of segments to repel each other */ +#define KSPRING_GROUPS 1.0e8 /* harmonic potential between segment groups */ +#define GROUP_WIDTH 0.05 /* interaction width of groups */ +#define GROUP_G_REPEL 1 /* set to 1 to add repulsion between centers of mass of groups */ +#define GROUP_G_REPEL_RADIUS 1.2 /* radius within which centers of mass of groups repel each other */ +#define TRACK_SEGMENT_GROUPS 1 /* set to 1 for view to track group of segments */ +#define TRACK_X_PADDING 2.0 /* distance from x boundary where tracking starts */ + +#define POSITION_DEPENDENT_TYPE 0 /* set to 1 to make particle type depend on initial position */ +#define POSITION_Y_DEPENDENCE 0 /* set to 1 for the separation between particles to be horizontal */ +#define PRINT_ENTROPY 0 /* set to 1 to compute entropy */ + +#define REACTION_DIFFUSION 0 /* set to 1 to simulate a chemical reaction (particles may change type) */ +#define RD_TYPES 3 /* number of types in reaction-diffusion equation */ +#define REACTION_PROB 0.0045 /* probability controlling reaction term */ + +#define PRINT_PARTICLE_NUMBER 0 /* set to 1 to print total number of particles */ +#define PRINT_LEFT 0 /* set to 1 to print certain parameters at the top left instead of right */ +#define PLOT_SPEEDS 1 /* set to 1 to add a plot of obstacle speeds (e.g. for rockets) */ +#define PLOT_TRAJECTORIES 1 /* set to 1 to add a plot of obstacle trajectories (e.g. for rockets) */ +#define VMAX_PLOT_SPEEDS 0.6 /* vertical scale of plot of obstacle speeds */ + +#define EHRENFEST_COPY 0 /* set to 1 to add equal number of larger particles (for Ehrenfest model) */ + +#define LID_MASS 1000.0 /* mass of lid for BC_RECTANGLE_LID b.c. */ +#define LID_WIDTH 0.1 /* width of lid for BC_RECTANGLE_LID b.c. */ +#define WALL_MASS 2000.0 /* mass of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_FRICTION 0.0 /* friction on wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_WIDTH 0.1 /* width of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_VMAX 100.0 /* max speed of wall */ +#define WALL_TIME 0 /* time during which to keep wall */ + +#define NXMAZE 10 /* width of maze */ +#define NYMAZE 10 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 200 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +#define FLOOR_FORCE 1 /* set to 1 to limit force on particle to FMAX */ +#define FMAX 1.0e12 /* maximal force */ +#define FLOOR_OMEGA 0 /* set to 1 to limit particle momentum to PMAX */ +#define PMAX 1000.0 /* maximal force */ + +#define HASHX 160 /* size of hashgrid in x direction */ +#define HASHY 600 /* size of hashgrid in y direction */ +#define HASHMAX 100 /* maximal number of particles per hashgrid cell */ +#define HASHGRID_PADDING 0.1 /* padding of hashgrid outside simulation window */ + +#define DRAW_COLOR_SCHEME 0 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 8.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 12.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +``` + +### 27 October 22 - An annular wave guide ### + +**Program:** `wave_3d.c` + +**Initial condition in function `animation()`:** `init_circular_wave_mod(-0.85, 0.0, phi, psi, xy_in);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 2000 /* number of grid points on x axis */ +#define NY 2000 /* number of grid points on y axis */ + +#define HIGHRES 1 /* set to 1 if resolution of grid is double that of displayed image */ + +#define XMIN -1.4 +#define XMAX 1.4 /* x interval */ +#define YMIN -1.4 +#define YMAX 1.4 /* y interval for 9/16 aspect ratio */ + +#define JULIA_SCALE 0.8 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 7 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 2 /* pattern of circles or polygons, see list in global_pdes.c */ + +#define COMPARISON 0 /* set to 1 to compare two different patterns */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ + +#define VARIABLE_IOR 0 /* set to 1 for a variable index of refraction */ +#define IOR 2 /* choice of index of refraction, see list in global_pdes.c */ +#define MANDEL_IOR_SCALE -0.05 /* parameter controlling dependence of IoR on Mandelbrot escape speed */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 1 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.7 /* parameter controlling the dimensions of domain */ +#define MU 0.0 /* parameter controlling the dimensions of domain */ +#define NPOLY 3 /* number of sides of polygon */ +#define APOLY 2.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 7 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 12 /* number of grid point for grid of disks */ +#define NGRIDY 16 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -2.9 +#define ISO_XSHIFT_RIGHT 1.4 +#define ISO_YSHIFT_LEFT -0.15 +#define ISO_YSHIFT_RIGHT -0.15 +#define ISO_SCALE 0.5 /* coordinates for isospectral billiards */ + + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard below */ + +/* Physical parameters of wave equation */ + +#define TWOSPEEDS 1 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OSCILLATE_LEFT 0 /* set to 1 to add oscilating boundary condition on the left */ +#define OSCILLATE_TOPBOT 0 /* set to 1 to enforce a planar wave on top and bottom boundary */ +#define OSCILLATION_SCHEDULE 3 /* oscillation schedule, see list in global_pdes.c */ + +#define OMEGA 0.001 /* frequency of periodic excitation */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.2 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COURANT 0.06 /* Courant number */ +#define COURANTB 0.15 /* Courant number in medium B */ +#define GAMMA 0.0 /* damping factor in wave equation */ +#define GAMMAB 0.015 /* damping factor in wave equation */ +#define GAMMA_SIDES 1.0e-4 /* damping factor on boundary */ +#define GAMMA_TOPBOT 1.0e-7 /* damping factor on boundary */ +#define KAPPA 0.0 /* "elasticity" term enforcing oscillations */ +#define KAPPA_SIDES 5.0e-4 /* "elasticity" term on absorbing boundary */ +#define KAPPA_TOPBOT 0.0 /* "elasticity" term on absorbing boundary */ +/* The Courant number is given by c*DT/DX, where DT is the time step and DX the lattice spacing */ +/* The physical damping coefficient is given by GAMMA/(DT)^2 */ +/* Increasing COURANT speeds up the simulation, but decreases accuracy */ +/* For similar wave forms, COURANT^2*GAMMA should be kept constant */ + +#define ADD_OSCILLATING_SOURCE 0 /* set to 1 to add an oscillating wave source */ +#define OSCILLATING_SOURCE_PERIOD 30 /* period of oscillating source */ + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 2 + +#define PRECOMPUTE_BC 0 /* set to 1 to compute neighbours for Laplacian in advance */ + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 1500 /* number of frames of movie */ +#define NVID 10 /* number of iterations between images displayed on screen */ +#define NSEG 1000 /* number of segments of boundary */ +#define INITIAL_TIME 0 /* time after which to start saving frames */ +#define BOUNDARY_WIDTH 2 /* width of billiard boundary */ +#define PRINT_SPEED 0 /* set to 1 to print speed of moving source */ + +#define PAUSE 100 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 100 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ +#define ROTATE_VIEW_WHILE_FADE 1 /* set to 1 to keep rotating viewpoint during fade */ + +/* Parameters of initial condition */ + +#define INITIAL_AMP 0.75 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.01 /* wavelength of initial condition */ + + +/* Plot type, see list in global_pdes.c */ + +#define ZPLOT 103 /* wave height */ +#define CPLOT 103 /* color scheme */ + +#define ZPLOT_B 105 +#define CPLOT_B 105 /* plot type for second movie */ + +#define AMPLITUDE_HIGH_RES 1 /* set to 1 to increase resolution of plot */ +#define SHADE_3D 1 /* set to 1 to change luminosity according to normal vector */ +#define NON_DIRICHLET_BC 0 /* set to 1 to draw only facets in domain, if field is not zero on boundary */ +#define FLOOR_ZCOORD 1 /* set to 1 to draw only facets with z not too negative */ +#define DRAW_BILLIARD 1 /* set to 1 to draw boundary */ +#define DRAW_BILLIARD_FRONT 1 /* set to 1 to draw front of boundary after drawing wave */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw construction lines of certain domains */ +#define FADE_IN_OBSTACLE 1 /* set to 1 to fade color inside obstacles */ +#define DRAW_OUTSIDE_GRAY 0 /* experimental, draw outside of billiard in gray */ + +#define PLOT_SCALE_ENERGY 0.01 /* vertical scaling in energy plot */ +#define PLOT_SCALE_LOG_ENERGY 0.25 /* vertical scaling in log energy plot */ + +/* 3D representation */ + +#define REPRESENTATION_3D 1 /* choice of 3D representation */ + +#define REP_AXO_3D 0 /* linear projection (axonometry) */ +#define REP_PROJ_3D 1 /* projection on plane orthogonal to observer line of sight */ + +#define ROTATE_VIEW 0 /* set to 1 to rotate position of observer */ +#define ROTATE_ANGLE 360.0 /* total angle of rotation during simulation */ + +/* Color schemes */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 16 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_pdes.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define VSCALE_AMPLITUDE 1.0 /* additional scaling factor for color scheme P_3D_AMPLITUDE */ +#define VSCALE_ENERGY 100.0 /* additional scaling factor for color scheme P_3D_ENERGY */ +#define PHASE_FACTOR 20.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define E_SCALE 100.0 /* scaling factor for energy representation */ +#define LOG_SCALE 0.5 /* scaling factor for energy log representation */ +#define LOG_SHIFT 0.5 /* shift of colors on log scale */ +#define LOG_ENERGY_FLOOR -10.0 /* floor value for log of (total) energy */ +#define LOG_MEAN_ENERGY_SHIFT 1.0 /* additional shift for log of mean energy */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 240.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -200.0 /* amplitude of variation of hue for color scheme C_HUE */ + +#define NXMAZE 7 /* width of maze */ +#define NYMAZE 7 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 24 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 2.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 5.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +#define SAVE_TIME_SERIES 0 /* set to 1 to save wave time series at a point */ + +/* For debugging purposes only */ +#define FLOOR 1 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ + +/* Parameters controlling 3D projection */ + +double u_3d[2] = {0.75, -0.45}; /* projections of basis vectors for REP_AXO_3D representation */ +double v_3d[2] = {-0.75, -0.45}; +double w_3d[2] = {0.0, 0.015}; +double light[3] = {0.816496581, -0.40824829, 0.40824829}; /* vector of "light" direction for P_3D_ANGLE color scheme */ +double observer[3] = {8.0, 8.0, 8.0}; /* location of observer for REP_PROJ_3D representation */ +int reset_view = 0; /* switch to reset 3D view parameters (for option ROTATE_VIEW) */ + +#define Z_SCALING_FACTOR 0.35 /* overall scaling factor of z axis for REP_PROJ_3D representation */ +#define XY_SCALING_FACTOR 2.4 /* overall scaling factor for on-screen (x,y) coordinates after projection */ +#define ZMAX_FACTOR 1.0 /* max value of z coordinate for REP_PROJ_3D representation */ +#define XSHIFT_3D -0.1 /* overall x shift for REP_PROJ_3D representation */ +#define YSHIFT_3D 0.1 /* overall y shift for REP_PROJ_3D representation */ + +``` + +### 26 October 22 - A shear flow ### + +**Program:** `rde.c` + +**Initial condition in function `animation()`:** `init_shear_flow(1.0, 0.02, 0.03, 1, 1, phi, xy_in);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 0 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1000 /* window width */ +#define WINHEIGHT 1000 /* window height */ + +#define NX 500 /* number of grid points on x axis */ +#define NY 500 /* number of grid points on y axis */ + +#define XMIN -1.5 +#define XMAX 1.5 /* x interval */ +#define YMIN -1.5 +#define YMAX 1.5 /* y interval for 9/16 aspect ratio */ + +/* Choice of simulated equation */ + +#define RDE_EQUATION 6 /* choice of reaction term, see list in global_3d.c */ +#define NFIELDS 2 /* number of fields in reaction-diffusion equation */ +#define NLAPLACIANS 1 /* number of fields for which to compute Laplacian */ + +#define ADD_POTENTIAL 0 /* set to 1 to add a potential (for Schrodinger equation) */ +#define ADD_MAGNETIC_FIELD 0 /* set to 1 to add a magnetic field (for Schrodinger equation) - then set POTENTIAL 1 */ +#define POTENTIAL 101 /* type of potential or vector potential, see list in global_3d.c */ + +#define ANTISYMMETRIZE_WAVE_FCT 0 /* set tot 1 to make wave function antisymmetric */ + +#define JULIA_SCALE 0.5 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 999 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 99 /* pattern of circles, see list in global_pdes.c */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 1.0 /* parameter controlling the dimensions of domain */ +#define MU 1.0 /* parameter controlling the dimensions of domain */ +#define NPOLY 5 /* number of sides of polygon */ +#define APOLY 2.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 7 /* depth of computation of Menger gasket */ +#define MRATIO 5 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 15 /* number of grid point for grid of disks */ +#define NGRIDY 20 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -1.65 +#define ISO_XSHIFT_RIGHT 0.4 +#define ISO_YSHIFT_LEFT -0.05 +#define ISO_YSHIFT_RIGHT -0.05 +#define ISO_SCALE 0.85 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard in sub_wave.c */ + +/* Physical patameters of wave equation */ + +#define DT 0.0000012 + +#define VISCOSITY 2.0 + +#define RPSA 0.75 /* parameter in Rock-Paper-Scissors-type interaction */ +#define RPSLZB 0.75 /* second parameter in Rock-Paper-Scissors-Lizard-Spock type interaction */ + +#define EPSILON 0.8 /* time scale separation */ +#define DELTA 0.1 /* time scale separation */ +#define FHNA 1.0 /* parameter in FHN equation */ +#define FHNC -0.01 /* parameter in FHN equation */ +#define K_HARMONIC 1.0 /* spring constant of harmonic potential */ +#define K_COULOMB 0.5 /* constant in Coulomb potential */ +#define BZQ 0.0008 /* parameter in BZ equation */ +#define BZF 1.2 /* parameter in BZ equation */ +#define B_FIELD 10.0 /* magnetic field */ +#define AB_RADIUS 0.2 /* radius of region with magnetic field for Aharonov-Bohm effect */ +#define K_EULER 50.0 /* constant in stream function integration of Euler equation */ + +#define SMOOTHEN_VORTICITY 1 /* set to 1 to smoothen vorticity field in Euler equation */ +#define SMOOTHEN_PERIOD 10 /* period between smoothenings */ +#define SMOOTH_FACTOR 0.015 /* factor by which to smoothen */ + +#define T_OUT 2.0 /* outside temperature */ +#define T_IN 0.0 /* inside temperature */ +#define SPEED 0.0 /* speed of drift to the right */ + +#define ADD_NOISE 0 /* set to 1 to add noise, set to 2 to add noise in right half */ +#define NOISE_INTENSITY 0.005 /* noise intensity */ +#define CHANGE_NOISE 1 /* set to 1 to increase noise intensity */ +#define NOISE_FACTOR 40.0 /* factor by which to increase noise intensity */ +#define NOISE_INITIAL_TIME 100 /* initial time during which noise remains constant */ + +#define CHANGE_VISCOSITY 0 /* set to 1 to change the viscosity in the course of the simulation */ +#define ADJUST_INTSTEP 0 /* set to 1 to decrease integration step when viscosity increases */ +#define VISCOSITY_INITIAL_TIME 10 /* initial time during which viscosity remains constant */ +#define VISCOSITY_FACTOR 100.0 /* factor by which to change viscosity */ +#define VISCOSITY_MAX 2.0 /* max value of viscosity beyond which NVID is increased and integration step is decrase, + for numerical stability */ + +#define CHANGE_RPSLZB 0 /* set to 1 to change second parameter in Rock-Paper-Scissors-Lizard-Spock equation */ +#define RPSLZB_CHANGE 0.75 /* factor by which to rpslzb parameter */ +#define RPSLZB_INITIAL_TIME 0 /* initial time during which rpslzb remains constant */ +#define RPSLZB_FINAL_TIME 500 /* final time during which rpslzb remains constant */ + + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 1 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 1000 /* number of frames of movie */ +#define NVID 200 /* number of iterations between images displayed on screen */ +#define ACCELERATION_FACTOR 1.0 /* factor by which to increase NVID in course of simulation */ +#define DT_ACCELERATION_FACTOR 1.0 /* factor by which to increase time step in course of simulation */ +#define MAX_DT 0.024 /* maximal value of integration step */ +#define NSEG 100 /* number of segments of boundary */ +#define BOUNDARY_WIDTH 5 /* width of billiard boundary */ + +#define PAUSE 100 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 2 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define INITIAL_TIME 0 /* initial still time */ +#define MID_FRAMES 50 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 50 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Visualisation */ + +#define PLOT_3D 0 /* controls whether plot is 2D or 3D */ + +#define ROTATE_VIEW 0 /* set to 1 to rotate position of observer */ +#define ROTATE_ANGLE 360.0 /* total angle of rotation during simulation */ + +/* Plot type - color scheme */ + +#define CPLOT 52 +#define CPLOT_B 51 + +/* Plot type - height of 3D plot */ + +#define ZPLOT 52 /* z coordinate in 3D plot */ +#define ZPLOT_B 51 /* z coordinate in second 3D plot */ + +#define AMPLITUDE_HIGH_RES 1 /* set to 1 to increase resolution of P_3D_AMPLITUDE plot */ +#define SHADE_3D 1 /* set to 1 to change luminosity according to normal vector */ +#define NON_DIRICHLET_BC 0 /* set to 1 to draw only facets in domain, if field is not zero on boundary */ +#define WRAP_ANGLE 1 /* experimental: wrap angle to [0, 2Pi) for interpolation in angle schemes */ +#define FADE_IN_OBSTACLE 0 /* set to 1 to fade color inside obstacles */ +#define DRAW_OUTSIDE_GRAY 0 /* experimental - draw outside of billiard in gray */ +#define ADD_POTENTIAL_TO_Z 1 /* set to 1 to add the external potential to z-coordinate of plot */ +#define ADD_POT_CONSTANT 0.5 /* constant in front of added potential */ + +#define PLOT_SCALE_ENERGY 0.05 /* vertical scaling in energy plot */ + +#define PRINT_TIME 0 /* set to 1 to print running time */ +#define PRINT_VISCOSITY 0 /* set to 1 to print viscosity */ +#define PRINT_RPSLZB 0 /* set to 1 to print rpslzb parameter */ +#define PRINT_PROBABILITIES 0 /* set to 1 to print probabilities (for Ehrenfest urn configuration) */ +#define PRINT_NOISE 0 /* set to 1 to print noise intensity */ + +#define DRAW_FIELD_LINES 0 /* set to 1 to draw field lines */ +#define FIELD_LINE_WIDTH 1 /* width of field lines */ +#define N_FIELD_LINES 120 /* number of field lines */ +#define FIELD_LINE_FACTOR 120 /* factor controlling precision when computing origin of field lines */ +#define DRAW_BILLIARD 1 /* set to 1 to draw boundary */ +#define DRAW_BILLIARD_FRONT 1 /* set to 1 to draw boundary */ +#define FILL_BILLIARD_COMPLEMENT 1 /* set to 1 to fill complement of billiard (for certain shapes only) */ + +/* 3D representation */ + +#define REPRESENTATION_3D 1 /* choice of 3D representation */ + +#define REP_AXO_3D 0 /* linear projection (axonometry) */ +#define REP_PROJ_3D 1 /* projection on plane orthogonal to observer line of sight */ + +/* Color schemes, see list in global_pdes.c */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 11 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* black background */ + +#define COLOR_SCHEME 3 /* choice of color scheme */ + +#define COLOR_PHASE_SHIFT 0.0 /* phase shift of color scheme, in units of Pi */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define VSCALE_AMPLITUDE 0.5 /* additional scaling factor for color scheme P_3D_AMPLITUDE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define CURL_SCALE 0.000015 /* scaling factor for curl representation */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ +#define SLOPE_SCHROD_LUM 50.0 /* sensitivity of luminosity on module, for color scheme Z_ARGUMENT */ +#define MIN_SCHROD_LUM 0.2 /* minimal luminosity in color scheme Z_ARGUMENT*/ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 359.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -359.0 /* amplitude of variation of hue for color scheme C_HUE */ +#define E_SCALE 100.0 /* scaling factor for energy representation */ +#define LOG_SCALE 0.75 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 + +#define DRAW_COLOR_SCHEME 0 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 3.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 2.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +/* only for compatibility with wave_common.c */ +#define TWOSPEEDS 0 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OMEGA 0.005 /* frequency of periodic excitation */ +#define COURANT 0.08 /* Courant number */ +#define COURANTB 0.03 /* Courant number in medium B */ +#define INITIAL_AMP 0.5 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.1 /* wavelength of initial condition */ +#define VSCALE_ENERGY 200.0 /* additional scaling factor for color scheme P_3D_ENERGY */ +#define PHASE_FACTOR 20.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define OSCILLATION_SCHEDULE 0 /* oscillation schedule, see list in global_pdes.c */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.2 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ +#define NXMAZE 8 /* width of maze */ +#define NYMAZE 8 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 58 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ +/* end of constants added only for compatibility with wave_common.c */ + + +double u_3d[2] = {0.75, -0.45}; /* projections of basis vectors for REP_AXO_3D representation */ +double v_3d[2] = {-0.75, -0.45}; +double w_3d[2] = {0.0, 0.015}; +double light[3] = {0.816496581, -0.40824829, 0.40824829}; /* vector of "light" direction for P_3D_ANGLE color scheme */ +double observer[3] = {8.0, 8.0, 8.0}; /* location of observer for REP_PROJ_3D representation */ +int reset_view = 0; /* switch to reset 3D view parameters (for option ROTATE_VIEW) */ + +#define Z_SCALING_FACTOR 0.25 /* overall scaling factor of z axis for REP_PROJ_3D representation */ +#define XY_SCALING_FACTOR 1.8 /* overall scaling factor for on-screen (x,y) coordinates after projection */ +#define ZMAX_FACTOR 1.0 /* max value of z coordinate for REP_PROJ_3D representation */ +#define XSHIFT_3D -0.1 /* overall x shift for REP_PROJ_3D representation */ +#define YSHIFT_3D 0.0 /* overall y shift for REP_PROJ_3D representation */ +#define BORDER_PADDING 2 /* distance from boundary at which to plot points, to avoid boundary effects due to gradient */ + +/* For debugging purposes only */ +#define FLOOR 1 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ +#define TEST_GRADIENT 0 /* print norm squared of gradient */ + +``` + +### 25 October 22 - Rocket comparison 9: Bell-shaped vs broad straight nozzle ### + +**Program:** `lennardjones.c` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 0 /* set to 1 to produce movies for wave height and energy simultaneously */ + +#define TIME_LAPSE 1 /* set to 1 to add a time-lapse movie at the end */ + /* so far incompatible with double movie */ +#define TIME_LAPSE_FACTOR 3 /* factor of time-lapse movie */ +#define TIME_LAPSE_FIRST 1 /* set to 1 to show time-lapse version first */ + +/* General geometrical parameters */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -3.3 +#define XMAX 4.7 /* x interval */ +#define YMIN -2.25 +#define YMAX 2.25 /* y interval for 9/16 aspect ratio */ + +#define INITXMIN -2.0 +#define INITXMAX 2.0 /* x interval for initial condition */ +#define INITYMIN -1.7 +#define INITYMAX 0.5 /* y interval for initial condition */ + +#define BCXMIN -5.1 +#define BCXMAX 6.1 /* x interval for boundary condition */ +#define BCYMIN -6.5 +#define BCYMAX 44.0 /* y interval for boundary condition */ + +#define OBSXMIN -2.0 +#define OBSXMAX 2.0 /* x interval for motion of obstacle */ + +#define CIRCLE_PATTERN 8 /* pattern of circles, see list in global_ljones.c */ + +#define ADD_FIXED_OBSTACLES 0 /* set to 1 do add fixed circular obstacles */ +#define OBSTACLE_PATTERN 3 /* pattern of obstacles, see list in global_ljones.c */ + +#define ADD_FIXED_SEGMENTS 1 /* set to 1 to add fixed segments as obstacles */ +#define SEGMENT_PATTERN 102 /* pattern of repelling segments, see list in global_ljones.c */ +#define ROCKET_SHAPE 1 /* shape of rocket combustion chamber, see list in global_ljones.c */ +#define ROCKET_SHAPE_B 1 /* shape of second rocket */ +#define NOZZLE_SHAPE 1 /* shape of nozzle, see list in global_ljones.c */ +#define NOZZLE_SHAPE_B 5 /* shape of nozzle for second rocket, see list in global_ljones.c */ + +#define TWO_TYPES 0 /* set to 1 to have two types of particles */ +#define TPYE_PROPORTION 0.5 /* proportion of particles of first type */ +#define SYMMETRIZE_FORCE 1 /* set to 1 to symmetrize two-particle interaction, only needed if particles are not all the same */ +#define CENTER_PX 0 /* set to 1 to center horizontal momentum */ +#define CENTER_PY 0 /* set to 1 to center vertical momentum */ +#define CENTER_PANGLE 0 /* set to 1 to center angular momentum */ + +#define INTERACTION 1 /* particle interaction, see list in global_ljones.c */ +#define INTERACTION_B 1 /* particle interaction for second type of particle, see list in global_ljones.c */ +#define SPIN_INTER_FREQUENCY 5.0 /* angular frequency of spin-spin interaction */ +#define SPIN_INTER_FREQUENCY_B 2.0 /* angular frequency of spin-spin interaction for second particle type */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 100 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define PDISC_DISTANCE 2.5 /* minimal distance in Poisson disc process, controls density of particles */ +#define PDISC_CANDIDATES 100 /* number of candidates in construction of Poisson disc process */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.8 /* parameter controlling the dimensions of domain */ +#define MU 0.009 /* parameter controlling radius of particles */ +#define MU_B 0.018 /* parameter controlling radius of particles of second type */ +#define NPOLY 25 /* number of sides of polygon */ +#define APOLY 0.666666666 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 4 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 90 /* number of grid point for grid of disks */ +#define NGRIDY 100 /* number of grid point for grid of disks */ +#define EHRENFEST_RADIUS 0.9 /* radius of container for Ehrenfest urn configuration */ +#define EHRENFEST_WIDTH 0.035 /* width of tube for Ehrenfest urn configuration */ +#define TWO_CIRCLES_RADIUS_RATIO 0.8 /* ratio of radii for S_TWO_CIRCLES_EXT segment configuration */ +#define DAM_WIDTH 0.05 /* width of dam for S_DAM segment configuration */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 3000 /* number of frames of movie */ +#define NVID 100 /* number of iterations between images displayed on screen */ +#define NSEG 250 /* number of segments of boundary */ +#define INITIAL_TIME 10 /* time after which to start saving frames */ +#define OBSTACLE_INITIAL_TIME 200 /* time after which to start moving obstacle */ +#define BOUNDARY_WIDTH 1 /* width of particle boundary */ +#define LINK_WIDTH 2 /* width of links between particles */ +#define CONTAINER_WIDTH 4 /* width of container boundary */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ + +/* Boundary conditions, see list in global_ljones.c */ + +#define BOUNDARY_COND 20 + +/* Plot type, see list in global_ljones.c */ + +#define PLOT 0 +#define PLOT_B 8 /* plot type for second movie */ + +#define DRAW_BONDS 0 /* set to 1 to draw bonds between neighbours */ +#define COLOR_BONDS 1 /* set to 1 to color bonds according to length */ +#define FILL_TRIANGLES 1 /* set to 1 to fill triangles between neighbours */ +#define COLOR_SEG_GROUPS 1 /* set to 1 to collor segment groups differently */ + +/* Color schemes */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_ljones.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_ljones.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 0.5 /* sensitivity of color on wave amplitude */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 220.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -50.0 /* amplitude of variation of hue for color scheme C_HUE */ + +/* particle properties */ + +#define ENERGY_HUE_MIN 330.0 /* color of original particle */ +#define ENERGY_HUE_MAX 50.0 /* color of saturated particle */ +#define PARTICLE_HUE_MIN 359.0 /* color of original particle */ +#define PARTICLE_HUE_MAX 0.0 /* color of saturated particle */ +#define PARTICLE_EMAX 2.0e2 /* energy of particle with hottest color */ +#define HUE_TYPE0 70.0 /* hue of particles of type 0 */ +#define HUE_TYPE1 280.0 /* hue of particles of type 1 */ +#define HUE_TYPE2 .0 /* hue of particles of type 2 */ +#define HUE_TYPE3 210.0 /* hue of particles of type 3 */ + +#define RANDOM_RADIUS 0 /* set to 1 for random circle radius */ +#define DT_PARTICLE 3.0e-6 /* time step for particle displacement */ +#define KREPEL 12.0 /* constant in repelling force between particles */ +#define EQUILIBRIUM_DIST 4.5 /* Lennard-Jones equilibrium distance */ +#define EQUILIBRIUM_DIST_B 3.5 /* Lennard-Jones equilibrium distance for second type of particle */ +#define REPEL_RADIUS 20.0 /* radius in which repelling force acts (in units of particle radius) */ +#define DAMPING 5.0 /* damping coefficient of particles */ +#define PARTICLE_MASS 1.0 /* mass of particle of radius MU */ +#define PARTICLE_MASS_B 1.0 /* mass of particle of radius MU */ +#define PARTICLE_INERTIA_MOMENT 0.2 /* moment of inertia of particle */ +#define PARTICLE_INERTIA_MOMENT_B 0.02 /* moment of inertia of second type of particle */ +#define V_INITIAL 0.0 /* initial velocity range */ +#define OMEGA_INITIAL 10.0 /* initial angular velocity range */ + +#define THERMOSTAT 1 /* set to 1 to switch on thermostat */ +#define VARY_THERMOSTAT 0 /* set to 1 for time-dependent thermostat schedule */ +#define SIGMA 5.0 /* noise intensity in thermostat */ +#define BETA 0.02 /* initial inverse temperature */ +#define MU_XI 0.01 /* friction constant in thermostat */ +#define KSPRING_BOUNDARY 1.0e7 /* confining harmonic potential outside simulation region */ +#define KSPRING_OBSTACLE 1.0e11 /* harmonic potential of obstacles */ +#define NBH_DIST_FACTOR 7.5 /* radius in which to count neighbours */ +#define GRAVITY 15.0 /* gravity acting on all particles */ +#define GRAVITY_X 0.0 /* horizontal gravity acting on all particles */ +#define INCREASE_GRAVITY 0 /* set to 1 to increase gravity during the simulation */ +#define GRAVITY_SCHEDULE 2 /* type of gravity schedule, see list in global_ljones.c */ +#define GRAVITY_FACTOR 100.0 /* factor by which to increase gravity */ +#define GRAVITY_INITIAL_TIME 200 /* time at start of simulation with constant gravity */ +#define GRAVITY_RESTORE_TIME 700 /* time at end of simulation with gravity restored to initial value */ + +#define ROTATION 0 /* set to 1 to include rotation of particles */ +#define COUPLE_ANGLE_TO_THERMOSTAT 0 /* set to 1 to couple angular degrees of freedom to thermostat */ +#define DIMENSION_FACTOR 1.0 /* scaling factor taking into account number of degrees of freedom */ +#define KTORQUE 100.0 /* force constant in angular dynamics */ +#define KTORQUE_B 10.0 /* force constant in angular dynamics */ +#define KTORQUE_DIFF 150.0 /* force constant in angular dynamics for different particles */ +#define DRAW_SPIN 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_SPIN_B 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_CROSS 1 /* set to 1 to draw cross on particles of second type */ +#define SPIN_RANGE 7.0 /* range of spin-spin interaction */ +#define SPIN_RANGE_B 5.0 /* range of spin-spin interaction for second type of particle */ +#define QUADRUPOLE_RATIO 0.6 /* anisotropy in quadrupole potential */ + +#define INCREASE_BETA 1 /* set to 1 to increase BETA during simulation */ +#define BETA_FACTOR 0.025 /* factor by which to change BETA during simulation */ +#define N_TOSCILLATIONS 1.5 /* number of temperature oscillations in BETA schedule */ +#define NO_OSCILLATION 1 /* set to 1 to have exponential BETA change only */ +#define MIDDLE_CONSTANT_PHASE 1400 /* final phase in which temperature is constant */ +#define FINAL_DECREASE_PHASE 1400 /* final phase in which temperature decreases */ +#define FINAL_CONSTANT_PHASE -1 /* final phase in which temperature is constant */ + +#define DECREASE_CONTAINER_SIZE 0 /* set to 1 to decrease size of container */ +#define SYMMETRIC_DECREASE 0 /* set tp 1 to decrease container symmetrically */ +#define COMPRESSION_RATIO 0.3 /* final size of container */ +#define RESTORE_CONTAINER_SIZE 1 /* set to 1 to restore container to initial size at end of simulation */ +#define RESTORE_TIME 700 /* time before end of sim at which to restore size */ + +#define MOVE_OBSTACLE 0 /* set to 1 to have a moving obstacle */ +#define CENTER_VIEW_ON_OBSTACLE 0 /* set to 1 to center display on moving obstacle */ +#define RESAMPLE_Y 0 /* set to 1 to resample y coordinate of moved particles (for shock waves) */ +#define NTRIALS 2000 /* number of trials when resampling */ +#define OBSTACLE_RADIUS 0.12 /* radius of obstacle for circle boundary conditions */ +#define FUNNEL_WIDTH 0.25 /* funnel width for funnel boundary conditions */ +#define OBSTACLE_XMIN 0.0 /* initial position of obstacle */ +#define OBSTACLE_XMAX 3.0 /* final position of obstacle */ +#define RECORD_PRESSURES 0 /* set to 1 to record pressures on obstacle */ +#define N_PRESSURES 100 /* number of intervals to record pressure */ +#define N_P_AVERAGE 100 /* size of pressure averaging window */ +#define N_T_AVERAGE 50 /* size of temperature averaging window */ +#define MAX_PRESSURE 3.0e10 /* pressure shown in "hottest" color */ +#define PARTIAL_THERMO_COUPLING 0 /* set to 1 to couple only particles to the right of obstacle to thermostat */ +#define PARTIAL_THERMO_REGION 1 /* region for partial thermostat coupling (see list in global_ljones.c) */ +#define PARTIAL_THERMO_SHIFT 0.2 /* distance from obstacle at the right of which particles are coupled to thermostat */ +#define PARTIAL_THERMO_WIDTH 0.5 /* vertical size of partial thermostat coupling */ +#define PARTIAL_THERMO_HEIGHT 0.2 /* vertical size of partial thermostat coupling */ + +#define INCREASE_KREPEL 0 /* set to 1 to increase KREPEL during simulation */ +#define KREPEL_FACTOR 1000.0 /* factor by which to change KREPEL during simulation */ + +#define PART_AT_BOTTOM 0 /* set to 1 to include "seed" particles at bottom */ +#define MASS_PART_BOTTOM 10000.0 /* mass of particles at bottom */ +#define NPART_BOTTOM 100 /* number of particles at the bottom */ + +#define ADD_PARTICLES 0 /* set to 1 to add particles */ +#define ADD_TIME 0 /* time at which to add first particle */ +#define ADD_PERIOD 10000 /* time interval between adding further particles */ +#define FINAL_NOADD_PERIOD 200 /* final period where no particles are added */ +#define SAFETY_FACTOR 2.0 /* no particles are added at distance less than MU*SAFETY_FACTOR of other particles */ + +#define TRACER_PARTICLE 0 /* set to 1 to have a tracer particle */ +#define N_TRACER_PARTICLES 3 /* number of tracer particles */ +#define TRAJECTORY_LENGTH 8000 /* length of recorded trajectory */ +#define TRACER_PARTICLE_MASS 4.0 /* relative mass of tracer particle */ +#define TRAJECTORY_WIDTH 3 /* width of tracer particle trajectory */ + +#define ROTATE_BOUNDARY 0 /* set to 1 to rotate the repelling segments */ +#define SMOOTH_ROTATION 1 /* set to 1 to update segments at each time step (rather than at each movie frame) */ +#define PERIOD_ROTATE_BOUNDARY 1000 /* period of rotating boundary */ +#define ROTATE_INITIAL_TIME 0 /* initial time without rotation */ +#define ROTATE_FINAL_TIME 100 /* final time without rotation */ +#define ROTATE_CHANGE_TIME 0.33 /* relative duration of acceleration/deceleration phases */ +#define OMEGAMAX 100.0 /* maximal rotation speed */ +#define PRINT_OMEGA 0 /* set to 1 to print angular speed */ +#define PRINT_PARTICLE_SPEEDS 0 /* set to 1 to print average speeds/momenta of particles */ +#define PRINT_SEGMENTS_SPEEDS 1 /* set to 1 to print velocity of moving segments */ + +#define MOVE_BOUNDARY 0 /* set to 1 to move repelling segments, due to force from particles */ +#define SEGMENTS_MASS 40.0 /* mass of collection of segments */ +#define DEACTIVATE_SEGMENT 1 /* set to 1 to deactivate last segment after a certain time */ +#define SEGMENT_DEACTIVATION_TIME 200 /* time at which to deactivate last segment */ +#define RELEASE_ROCKET_AT_DEACTIVATION 1 /* set to 1 to limit segments velocity before segment release */ +#define SEGMENTS_X0 1.5 /* initial position of segments */ +#define SEGMENTS_Y0 0.0 /* initial position of segments */ +#define SEGMENTS_VX0 0.0 /* initial velocity of segments */ +#define SEGMENTS_VY0 0.0 /* initial velocity of segments */ +#define DAMP_SEGS_AT_NEGATIVE_Y 0 /* set to 1 to dampen segments when y coordinate is negative */ + +#define MOVE_SEGMENT_GROUPS 1 /* set to 1 to group segments into moving units */ +#define SEGMENT_GROUP_MASS 1000.0 /* mass of segment group */ +#define SEGMENT_GROUP_I 35.0 /* moment of inertia of segment group */ +#define SEGMENT_GROUP_DAMPING 0.0 /* damping of segment groups */ +#define GROUP_REPULSION 1 /* set to 1 for groups of segments to repel each other */ +#define KSPRING_GROUPS 1.0e8 /* harmonic potential between segment groups */ +#define GROUP_WIDTH 0.05 /* interaction width of groups */ +#define GROUP_G_REPEL 1 /* set to 1 to add repulsion between centers of mass of groups */ +#define GROUP_G_REPEL_RADIUS 1.2 /* radius within which centers of mass of groups repel each other */ +#define TRACK_SEGMENT_GROUPS 1 /* set to 1 for view to track group of segments */ +#define TRACK_X_PADDING 2.0 /* distance from x boundary where tracking starts */ + +#define POSITION_DEPENDENT_TYPE 0 /* set to 1 to make particle type depend on initial position */ +#define POSITION_Y_DEPENDENCE 0 /* set to 1 for the separation between particles to be horizontal */ +#define PRINT_ENTROPY 0 /* set to 1 to compute entropy */ + +#define REACTION_DIFFUSION 0 /* set to 1 to simulate a chemical reaction (particles may change type) */ +#define RD_TYPES 3 /* number of types in reaction-diffusion equation */ +#define REACTION_PROB 0.0045 /* probability controlling reaction term */ + +#define PRINT_PARTICLE_NUMBER 0 /* set to 1 to print total number of particles */ +#define PRINT_LEFT 0 /* set to 1 to print certain parameters at the top left instead of right */ +#define PLOT_SPEEDS 1 /* set to 1 to add a plot of obstacle speeds (e.g. for rockets) */ +#define PLOT_TRAJECTORIES 1 /* set to 1 to add a plot of obstacle trajectories (e.g. for rockets) */ +#define VMAX_PLOT_SPEEDS 0.6 /* vertical scale of plot of obstacle speeds */ + +#define EHRENFEST_COPY 0 /* set to 1 to add equal number of larger particles (for Ehrenfest model) */ + +#define LID_MASS 1000.0 /* mass of lid for BC_RECTANGLE_LID b.c. */ +#define LID_WIDTH 0.1 /* width of lid for BC_RECTANGLE_LID b.c. */ +#define WALL_MASS 2000.0 /* mass of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_FRICTION 0.0 /* friction on wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_WIDTH 0.1 /* width of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_VMAX 100.0 /* max speed of wall */ +#define WALL_TIME 0 /* time during which to keep wall */ + +#define NXMAZE 10 /* width of maze */ +#define NYMAZE 10 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 200 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +#define FLOOR_FORCE 1 /* set to 1 to limit force on particle to FMAX */ +#define FMAX 1.0e12 /* maximal force */ +#define FLOOR_OMEGA 0 /* set to 1 to limit particle momentum to PMAX */ +#define PMAX 1000.0 /* maximal force */ + +#define HASHX 160 /* size of hashgrid in x direction */ +#define HASHY 600 /* size of hashgrid in y direction */ +#define HASHMAX 100 /* maximal number of particles per hashgrid cell */ +#define HASHGRID_PADDING 0.1 /* padding of hashgrid outside simulation window */ + +#define DRAW_COLOR_SCHEME 0 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 8.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 12.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +``` + +### 24 October 22 - Why the Wifi s*cks in your flat ### + +**Program:** `wave_billiard.c` + +**Initial condition in function `animation()`:** +``` + init_circular_wave(0.0, 0.3, phi, psi, xy_in); + sign = -sign; + add_circular_wave(sign, 0.0, 0.3, phi, psi, xy_in); +``` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 3840 /* number of grid points on x axis */ +#define NY 2000 /* number of grid points on y axis */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +#define HIGHRES 1 /* set to 1 if resolution of grid is double that of displayed image */ + +#define JULIA_SCALE 1.0 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 53 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 1 /* pattern of circles or polygons, see list in global_pdes.c */ + +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 1 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 1.0 /* parameter controlling the dimensions of domain */ +#define MU 0.3 /* parameter controlling the dimensions of domain */ +#define NPOLY 6 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 6 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 12 /* number of grid point for grid of disks */ +#define NGRIDY 15 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -2.9 +#define ISO_XSHIFT_RIGHT 1.4 +#define ISO_YSHIFT_LEFT -0.15 +#define ISO_YSHIFT_RIGHT -0.15 +#define ISO_SCALE 0.5 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard below */ + +/* Physical parameters of wave equation */ + +#define TWOSPEEDS 1 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OSCILLATE_LEFT 0 /* set to 1 to add oscilating boundary condition on the left */ +#define OSCILLATE_TOPBOT 0 /* set to 1 to enforce a planar wave on top and bottom boundary */ +#define OSCILLATION_SCHEDULE 1 /* oscillation schedule, see list in global_pdes.c */ + +#define OMEGA 0.0005 /* frequency of periodic excitation */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.25 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COURANT 0.1 /* Courant number */ +#define COURANTB 0.05 /* Courant number in medium B */ +#define GAMMA 0.0 /* damping factor in wave equation */ +#define GAMMAB 5.0e-3 /* damping factor in wave equation */ +#define GAMMA_SIDES 1.0e-4 /* damping factor on boundary */ +#define GAMMA_TOPBOT 1.0e-7 /* damping factor on boundary */ +#define KAPPA 0.0 /* "elasticity" term enforcing oscillations */ +#define KAPPA_SIDES 5.0e-4 /* "elasticity" term on absorbing boundary */ +#define KAPPA_TOPBOT 0.0 /* "elasticity" term on absorbing boundary */ +/* The Courant number is given by c*DT/DX, where DT is the time step and DX the lattice spacing */ +/* The physical damping coefficient is given by GAMMA/(DT)^2 */ +/* Increasing COURANT speeds up the simulation, but decreases accuracy */ +/* For similar wave forms, COURANT^2*GAMMA should be kept constant */ + +#define ADD_OSCILLATING_SOURCE 1 /* set to 1 to add an oscillating wave source */ +#define OSCILLATING_SOURCE_PERIOD 50 /* period of oscillating source */ + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 2 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 2400 /* number of frames of movie */ +#define NVID 12 /* number of iterations between images displayed on screen */ +#define NSEG 1000 /* number of segments of boundary */ +#define INITIAL_TIME 0 /* time after which to start saving frames */ +#define BOUNDARY_WIDTH 2 /* width of billiard boundary */ +#define PRINT_SPEED 0 /* print speed of moving source */ + +#define PAUSE 200 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Parameters of initial condition */ + +#define INITIAL_AMP 1.0 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.01 /* wavelength of initial condition */ + +/* Plot type, see list in global_pdes.c */ + +#define PLOT 0 + +#define PLOT_B 5 /* plot type for second movie */ + +/* Color schemes */ + +#define COLOR_PALETTE 17 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 13 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_pdes.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define PHASE_FACTOR 1.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define E_SCALE 200.0 /* scaling factor for energy representation */ +#define LOG_SCALE 1.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 /* shift of colors on log scale */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 180.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -180.0 /* amplitude of variation of hue for color scheme C_HUE */ + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 1.5 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 1.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +#define SAVE_TIME_SERIES 0 /* set to 1 to save wave time series at a point */ + +#define NXMAZE 7 /* width of maze */ +#define NYMAZE 7 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 24 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +/* For debugging purposes only */ +#define FLOOR 0 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ + +``` + +### 23 October 22 - Jovian weather: A shear flow under the incompressible Euler equation ### + +**Program:** `rde.c` + +**Initial condition in function `animation()`:** `init_shear_flow(0.05, 0.2, phi, xy_in);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ + +#define NX 960 /* number of grid points on x axis */ +#define NY 500 /* number of grid points on y axis */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +/* Choice of simulated equation */ + +#define RDE_EQUATION 6 /* choice of reaction term, see list in global_3d.c */ +#define NFIELDS 2 /* number of fields in reaction-diffusion equation */ +#define NLAPLACIANS 1 /* number of fields for which to compute Laplacian */ + +#define ADD_POTENTIAL 0 /* set to 1 to add a potential (for Schrodinger equation) */ +#define ADD_MAGNETIC_FIELD 0 /* set to 1 to add a magnetic field (for Schrodinger equation) - then set POTENTIAL 1 */ +#define POTENTIAL 101 /* type of potential or vector potential, see list in global_3d.c */ + +#define ANTISYMMETRIZE_WAVE_FCT 0 /* set tot 1 to make wave function antisymmetric */ + +#define JULIA_SCALE 0.5 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 999 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 99 /* pattern of circles, see list in global_pdes.c */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 1.0 /* parameter controlling the dimensions of domain */ +#define MU 1.0 /* parameter controlling the dimensions of domain */ +#define NPOLY 5 /* number of sides of polygon */ +#define APOLY 2.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 7 /* depth of computation of Menger gasket */ +#define MRATIO 5 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 15 /* number of grid point for grid of disks */ +#define NGRIDY 20 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -1.65 +#define ISO_XSHIFT_RIGHT 0.4 +#define ISO_YSHIFT_LEFT -0.05 +#define ISO_YSHIFT_RIGHT -0.05 +#define ISO_SCALE 0.85 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard in sub_wave.c */ + +/* Physical patameters of wave equation */ + +#define DT 0.0000012 + +#define VISCOSITY 2.0 + +#define RPSA 0.75 /* parameter in Rock-Paper-Scissors-type interaction */ +#define RPSLZB 0.75 /* second parameter in Rock-Paper-Scissors-Lizard-Spock type interaction */ + +#define EPSILON 0.8 /* time scale separation */ +#define DELTA 0.1 /* time scale separation */ +#define FHNA 1.0 /* parameter in FHN equation */ +#define FHNC -0.01 /* parameter in FHN equation */ +#define K_HARMONIC 1.0 /* spring constant of harmonic potential */ +#define K_COULOMB 0.5 /* constant in Coulomb potential */ +#define BZQ 0.0008 /* parameter in BZ equation */ +#define BZF 1.2 /* parameter in BZ equation */ +#define B_FIELD 10.0 /* magnetic field */ +#define AB_RADIUS 0.2 /* radius of region with magnetic field for Aharonov-Bohm effect */ +#define K_EULER 50.0 /* constant in stream function integration of Euler equation */ + +#define SMOOTHEN_VORTICITY 1 /* set to 1 to smoothen vorticity field in Euler equation */ +#define SMOOTHEN_PERIOD 10 /* period between smoothenings */ +#define SMOOTH_FACTOR 0.015 /* factor by which to smoothen */ + +#define T_OUT 2.0 /* outside temperature */ +#define T_IN 0.0 /* inside temperature */ +#define SPEED 0.0 /* speed of drift to the right */ + +#define ADD_NOISE 0 /* set to 1 to add noise, set to 2 to add noise in right half */ +#define NOISE_INTENSITY 0.005 /* noise intensity */ +#define CHANGE_NOISE 1 /* set to 1 to increase noise intensity */ +#define NOISE_FACTOR 40.0 /* factor by which to increase noise intensity */ +#define NOISE_INITIAL_TIME 100 /* initial time during which noise remains constant */ + +#define CHANGE_VISCOSITY 0 /* set to 1 to change the viscosity in the course of the simulation */ +#define ADJUST_INTSTEP 0 /* set to 1 to decrease integration step when viscosity increases */ +#define VISCOSITY_INITIAL_TIME 10 /* initial time during which viscosity remains constant */ +#define VISCOSITY_FACTOR 100.0 /* factor by which to change viscosity */ +#define VISCOSITY_MAX 2.0 /* max value of viscosity beyond which NVID is increased and integration step is decrase, + for numerical stability */ + +#define CHANGE_RPSLZB 0 /* set to 1 to change second parameter in Rock-Paper-Scissors-Lizard-Spock equation */ +#define RPSLZB_CHANGE 0.75 /* factor by which to rpslzb parameter */ +#define RPSLZB_INITIAL_TIME 0 /* initial time during which rpslzb remains constant */ +#define RPSLZB_FINAL_TIME 500 /* final time during which rpslzb remains constant */ + + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 1 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 2300 /* number of frames of movie */ +#define NVID 100 /* number of iterations between images displayed on screen */ +#define ACCELERATION_FACTOR 1.0 /* factor by which to increase NVID in course of simulation */ +#define DT_ACCELERATION_FACTOR 1.0 /* factor by which to increase time step in course of simulation */ +#define MAX_DT 0.024 /* maximal value of integration step */ +#define NSEG 100 /* number of segments of boundary */ +#define BOUNDARY_WIDTH 5 /* width of billiard boundary */ + +#define PAUSE 100 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 2 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define INITIAL_TIME 0 /* initial still time */ +#define MID_FRAMES 50 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 50 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Visualisation */ + +#define PLOT_3D 0 /* controls whether plot is 2D or 3D */ + +#define ROTATE_VIEW 0 /* set to 1 to rotate position of observer */ +#define ROTATE_ANGLE 360.0 /* total angle of rotation during simulation */ + +/* Plot type - color scheme */ + +#define CPLOT 52 +#define CPLOT_B 51 + +/* Plot type - height of 3D plot */ + +#define ZPLOT 52 /* z coordinate in 3D plot */ +#define ZPLOT_B 51 /* z coordinate in second 3D plot */ + +#define AMPLITUDE_HIGH_RES 1 /* set to 1 to increase resolution of P_3D_AMPLITUDE plot */ +#define SHADE_3D 1 /* set to 1 to change luminosity according to normal vector */ +#define NON_DIRICHLET_BC 0 /* set to 1 to draw only facets in domain, if field is not zero on boundary */ +#define WRAP_ANGLE 1 /* experimental: wrap angle to [0, 2Pi) for interpolation in angle schemes */ +#define FADE_IN_OBSTACLE 0 /* set to 1 to fade color inside obstacles */ +#define DRAW_OUTSIDE_GRAY 0 /* experimental - draw outside of billiard in gray */ +#define ADD_POTENTIAL_TO_Z 1 /* set to 1 to add the external potential to z-coordinate of plot */ +#define ADD_POT_CONSTANT 0.5 /* constant in front of added potential */ + +#define PLOT_SCALE_ENERGY 0.05 /* vertical scaling in energy plot */ + +#define PRINT_TIME 0 /* set to 1 to print running time */ +#define PRINT_VISCOSITY 0 /* set to 1 to print viscosity */ +#define PRINT_RPSLZB 0 /* set to 1 to print rpslzb parameter */ +#define PRINT_PROBABILITIES 0 /* set to 1 to print probabilities (for Ehrenfest urn configuration) */ +#define PRINT_NOISE 0 /* set to 1 to print noise intensity */ + +#define DRAW_FIELD_LINES 0 /* set to 1 to draw field lines */ +#define FIELD_LINE_WIDTH 1 /* width of field lines */ +#define N_FIELD_LINES 120 /* number of field lines */ +#define FIELD_LINE_FACTOR 120 /* factor controlling precision when computing origin of field lines */ +#define DRAW_BILLIARD 1 /* set to 1 to draw boundary */ +#define DRAW_BILLIARD_FRONT 1 /* set to 1 to draw boundary */ +#define FILL_BILLIARD_COMPLEMENT 1 /* set to 1 to fill complement of billiard (for certain shapes only) */ + +/* 3D representation */ + +#define REPRESENTATION_3D 1 /* choice of 3D representation */ + +#define REP_AXO_3D 0 /* linear projection (axonometry) */ +#define REP_PROJ_3D 1 /* projection on plane orthogonal to observer line of sight */ + +/* Color schemes, see list in global_pdes.c */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 14 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* black background */ + +#define COLOR_SCHEME 3 /* choice of color scheme */ + +#define COLOR_PHASE_SHIFT 0.0 /* phase shift of color scheme, in units of Pi */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define VSCALE_AMPLITUDE 2.0 /* additional scaling factor for color scheme P_3D_AMPLITUDE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define CURL_SCALE 0.000015 /* scaling factor for curl representation */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ +#define SLOPE_SCHROD_LUM 50.0 /* sensitivity of luminosity on module, for color scheme Z_ARGUMENT */ +#define MIN_SCHROD_LUM 0.2 /* minimal luminosity in color scheme Z_ARGUMENT*/ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 359.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -359.0 /* amplitude of variation of hue for color scheme C_HUE */ +#define E_SCALE 100.0 /* scaling factor for energy representation */ +#define LOG_SCALE 1.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 3.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 2.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +/* only for compatibility with wave_common.c */ +#define TWOSPEEDS 0 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OMEGA 0.005 /* frequency of periodic excitation */ +#define COURANT 0.08 /* Courant number */ +#define COURANTB 0.03 /* Courant number in medium B */ +#define INITIAL_AMP 0.5 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.1 /* wavelength of initial condition */ +#define VSCALE_ENERGY 200.0 /* additional scaling factor for color scheme P_3D_ENERGY */ +#define PHASE_FACTOR 20.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define OSCILLATION_SCHEDULE 0 /* oscillation schedule, see list in global_pdes.c */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.2 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ +#define NXMAZE 8 /* width of maze */ +#define NYMAZE 8 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 58 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ +/* end of constants added only for compatibility with wave_common.c */ + + +double u_3d[2] = {0.75, -0.45}; /* projections of basis vectors for REP_AXO_3D representation */ +double v_3d[2] = {-0.75, -0.45}; +double w_3d[2] = {0.0, 0.015}; +double light[3] = {0.816496581, -0.40824829, 0.40824829}; /* vector of "light" direction for P_3D_ANGLE color scheme */ +double observer[3] = {8.0, 8.0, 8.0}; /* location of observer for REP_PROJ_3D representation */ +int reset_view = 0; /* switch to reset 3D view parameters (for option ROTATE_VIEW) */ + +#define Z_SCALING_FACTOR 1.0 /* overall scaling factor of z axis for REP_PROJ_3D representation */ +#define XY_SCALING_FACTOR 1.8 /* overall scaling factor for on-screen (x,y) coordinates after projection */ +#define ZMAX_FACTOR 1.0 /* max value of z coordinate for REP_PROJ_3D representation */ +#define XSHIFT_3D -0.1 /* overall x shift for REP_PROJ_3D representation */ +#define YSHIFT_3D 0.0 /* overall y shift for REP_PROJ_3D representation */ +#define BORDER_PADDING 2 /* distance from boundary at which to plot points, to avoid boundary effects due to gradient */ + +/* For debugging purposes only */ +#define FLOOR 1 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ +#define TEST_GRADIENT 0 /* print norm squared of gradient */ + +``` + +### 22 October 22 - Rocket comparison 8 – with an unexpected outcome ### + +**Program:** `lennardjones.c` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 0 /* set to 1 to produce movies for wave height and energy simultaneously */ + +#define TIME_LAPSE 1 /* set to 1 to add a time-lapse movie at the end */ + /* so far incompatible with double movie */ +#define TIME_LAPSE_FACTOR 3 /* factor of time-lapse movie */ +#define TIME_LAPSE_FIRST 1 /* set to 1 to show time-lapse version first */ + +/* General geometrical parameters */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -3.3 +#define XMAX 4.7 /* x interval */ +#define YMIN -2.25 +#define YMAX 2.25 /* y interval for 9/16 aspect ratio */ + +#define INITXMIN -2.0 +#define INITXMAX 2.0 /* x interval for initial condition */ +#define INITYMIN -1.7 +#define INITYMAX 0.5 /* y interval for initial condition */ + +#define BCXMIN -5.1 +#define BCXMAX 6.1 /* x interval for boundary condition */ +#define BCYMIN -6.5 +#define BCYMAX 44.0 /* y interval for boundary condition */ + +#define OBSXMIN -2.0 +#define OBSXMAX 2.0 /* x interval for motion of obstacle */ + +#define CIRCLE_PATTERN 8 /* pattern of circles, see list in global_ljones.c */ + +#define ADD_FIXED_OBSTACLES 0 /* set to 1 do add fixed circular obstacles */ +#define OBSTACLE_PATTERN 3 /* pattern of obstacles, see list in global_ljones.c */ + +#define ADD_FIXED_SEGMENTS 1 /* set to 1 to add fixed segments as obstacles */ +#define SEGMENT_PATTERN 102 /* pattern of repelling segments, see list in global_ljones.c */ +#define ROCKET_SHAPE 1 /* shape of rocket combustion chamber, see list in global_ljones.c */ +#define ROCKET_SHAPE_B 1 /* shape of second rocket */ +#define NOZZLE_SHAPE 1 /* shape of nozzle, see list in global_ljones.c */ +#define NOZZLE_SHAPE_B 4 /* shape of nozzle for second rocket, see list in global_ljones.c */ + +#define TWO_TYPES 0 /* set to 1 to have two types of particles */ +#define TPYE_PROPORTION 0.5 /* proportion of particles of first type */ +#define SYMMETRIZE_FORCE 1 /* set to 1 to symmetrize two-particle interaction, only needed if particles are not all the same */ +#define CENTER_PX 0 /* set to 1 to center horizontal momentum */ +#define CENTER_PY 0 /* set to 1 to center vertical momentum */ +#define CENTER_PANGLE 0 /* set to 1 to center angular momentum */ + +#define INTERACTION 1 /* particle interaction, see list in global_ljones.c */ +#define INTERACTION_B 1 /* particle interaction for second type of particle, see list in global_ljones.c */ +#define SPIN_INTER_FREQUENCY 5.0 /* angular frequency of spin-spin interaction */ +#define SPIN_INTER_FREQUENCY_B 2.0 /* angular frequency of spin-spin interaction for second particle type */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 100 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define PDISC_DISTANCE 2.5 /* minimal distance in Poisson disc process, controls density of particles */ +#define PDISC_CANDIDATES 100 /* number of candidates in construction of Poisson disc process */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.8 /* parameter controlling the dimensions of domain */ +#define MU 0.009 /* parameter controlling radius of particles */ +#define MU_B 0.018 /* parameter controlling radius of particles of second type */ +#define NPOLY 25 /* number of sides of polygon */ +#define APOLY 0.666666666 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 4 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 90 /* number of grid point for grid of disks */ +#define NGRIDY 100 /* number of grid point for grid of disks */ +#define EHRENFEST_RADIUS 0.9 /* radius of container for Ehrenfest urn configuration */ +#define EHRENFEST_WIDTH 0.035 /* width of tube for Ehrenfest urn configuration */ +#define TWO_CIRCLES_RADIUS_RATIO 0.8 /* ratio of radii for S_TWO_CIRCLES_EXT segment configuration */ +#define DAM_WIDTH 0.05 /* width of dam for S_DAM segment configuration */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 3250 /* number of frames of movie */ +#define NVID 100 /* number of iterations between images displayed on screen */ +#define NSEG 250 /* number of segments of boundary */ +#define INITIAL_TIME 10 /* time after which to start saving frames */ +#define OBSTACLE_INITIAL_TIME 200 /* time after which to start moving obstacle */ +#define BOUNDARY_WIDTH 1 /* width of particle boundary */ +#define LINK_WIDTH 2 /* width of links between particles */ +#define CONTAINER_WIDTH 4 /* width of container boundary */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ + +/* Boundary conditions, see list in global_ljones.c */ + +#define BOUNDARY_COND 20 + +/* Plot type, see list in global_ljones.c */ + +#define PLOT 0 +#define PLOT_B 8 /* plot type for second movie */ + +#define DRAW_BONDS 0 /* set to 1 to draw bonds between neighbours */ +#define COLOR_BONDS 1 /* set to 1 to color bonds according to length */ +#define FILL_TRIANGLES 1 /* set to 1 to fill triangles between neighbours */ +#define COLOR_SEG_GROUPS 1 /* set to 1 to collor segment groups differently */ + +/* Color schemes */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_ljones.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_ljones.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 0.5 /* sensitivity of color on wave amplitude */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 220.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -50.0 /* amplitude of variation of hue for color scheme C_HUE */ + +/* particle properties */ + +#define ENERGY_HUE_MIN 330.0 /* color of original particle */ +#define ENERGY_HUE_MAX 50.0 /* color of saturated particle */ +#define PARTICLE_HUE_MIN 359.0 /* color of original particle */ +#define PARTICLE_HUE_MAX 0.0 /* color of saturated particle */ +#define PARTICLE_EMAX 2.0e2 /* energy of particle with hottest color */ +#define HUE_TYPE0 70.0 /* hue of particles of type 0 */ +#define HUE_TYPE1 280.0 /* hue of particles of type 1 */ +#define HUE_TYPE2 .0 /* hue of particles of type 2 */ +#define HUE_TYPE3 210.0 /* hue of particles of type 3 */ + +#define RANDOM_RADIUS 0 /* set to 1 for random circle radius */ +#define DT_PARTICLE 3.0e-6 /* time step for particle displacement */ +#define KREPEL 12.0 /* constant in repelling force between particles */ +#define EQUILIBRIUM_DIST 4.5 /* Lennard-Jones equilibrium distance */ +#define EQUILIBRIUM_DIST_B 3.5 /* Lennard-Jones equilibrium distance for second type of particle */ +#define REPEL_RADIUS 20.0 /* radius in which repelling force acts (in units of particle radius) */ +#define DAMPING 5.0 /* damping coefficient of particles */ +#define PARTICLE_MASS 1.0 /* mass of particle of radius MU */ +#define PARTICLE_MASS_B 1.0 /* mass of particle of radius MU */ +#define PARTICLE_INERTIA_MOMENT 0.2 /* moment of inertia of particle */ +#define PARTICLE_INERTIA_MOMENT_B 0.02 /* moment of inertia of second type of particle */ +#define V_INITIAL 0.0 /* initial velocity range */ +#define OMEGA_INITIAL 10.0 /* initial angular velocity range */ + +#define THERMOSTAT 1 /* set to 1 to switch on thermostat */ +#define VARY_THERMOSTAT 0 /* set to 1 for time-dependent thermostat schedule */ +#define SIGMA 5.0 /* noise intensity in thermostat */ +#define BETA 0.02 /* initial inverse temperature */ +#define MU_XI 0.01 /* friction constant in thermostat */ +#define KSPRING_BOUNDARY 1.0e7 /* confining harmonic potential outside simulation region */ +#define KSPRING_OBSTACLE 1.0e11 /* harmonic potential of obstacles */ +#define NBH_DIST_FACTOR 7.5 /* radius in which to count neighbours */ +#define GRAVITY 15.0 /* gravity acting on all particles */ +#define GRAVITY_X 0.0 /* horizontal gravity acting on all particles */ +#define INCREASE_GRAVITY 0 /* set to 1 to increase gravity during the simulation */ +#define GRAVITY_SCHEDULE 2 /* type of gravity schedule, see list in global_ljones.c */ +#define GRAVITY_FACTOR 100.0 /* factor by which to increase gravity */ +#define GRAVITY_INITIAL_TIME 200 /* time at start of simulation with constant gravity */ +#define GRAVITY_RESTORE_TIME 700 /* time at end of simulation with gravity restored to initial value */ + +#define ROTATION 0 /* set to 1 to include rotation of particles */ +#define COUPLE_ANGLE_TO_THERMOSTAT 0 /* set to 1 to couple angular degrees of freedom to thermostat */ +#define DIMENSION_FACTOR 1.0 /* scaling factor taking into account number of degrees of freedom */ +#define KTORQUE 100.0 /* force constant in angular dynamics */ +#define KTORQUE_B 10.0 /* force constant in angular dynamics */ +#define KTORQUE_DIFF 150.0 /* force constant in angular dynamics for different particles */ +#define DRAW_SPIN 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_SPIN_B 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_CROSS 1 /* set to 1 to draw cross on particles of second type */ +#define SPIN_RANGE 7.0 /* range of spin-spin interaction */ +#define SPIN_RANGE_B 5.0 /* range of spin-spin interaction for second type of particle */ +#define QUADRUPOLE_RATIO 0.6 /* anisotropy in quadrupole potential */ + +#define INCREASE_BETA 1 /* set to 1 to increase BETA during simulation */ +#define BETA_FACTOR 0.025 /* factor by which to change BETA during simulation */ +#define N_TOSCILLATIONS 1.5 /* number of temperature oscillations in BETA schedule */ +#define NO_OSCILLATION 1 /* set to 1 to have exponential BETA change only */ +#define MIDDLE_CONSTANT_PHASE 1550 /* final phase in which temperature is constant */ +#define FINAL_DECREASE_PHASE 1500 /* final phase in which temperature decreases */ +#define FINAL_CONSTANT_PHASE -1 /* final phase in which temperature is constant */ + +#define DECREASE_CONTAINER_SIZE 0 /* set to 1 to decrease size of container */ +#define SYMMETRIC_DECREASE 0 /* set tp 1 to decrease container symmetrically */ +#define COMPRESSION_RATIO 0.3 /* final size of container */ +#define RESTORE_CONTAINER_SIZE 1 /* set to 1 to restore container to initial size at end of simulation */ +#define RESTORE_TIME 700 /* time before end of sim at which to restore size */ + +#define MOVE_OBSTACLE 0 /* set to 1 to have a moving obstacle */ +#define CENTER_VIEW_ON_OBSTACLE 0 /* set to 1 to center display on moving obstacle */ +#define RESAMPLE_Y 0 /* set to 1 to resample y coordinate of moved particles (for shock waves) */ +#define NTRIALS 2000 /* number of trials when resampling */ +#define OBSTACLE_RADIUS 0.12 /* radius of obstacle for circle boundary conditions */ +#define FUNNEL_WIDTH 0.25 /* funnel width for funnel boundary conditions */ +#define OBSTACLE_XMIN 0.0 /* initial position of obstacle */ +#define OBSTACLE_XMAX 3.0 /* final position of obstacle */ +#define RECORD_PRESSURES 0 /* set to 1 to record pressures on obstacle */ +#define N_PRESSURES 100 /* number of intervals to record pressure */ +#define N_P_AVERAGE 100 /* size of pressure averaging window */ +#define N_T_AVERAGE 50 /* size of temperature averaging window */ +#define MAX_PRESSURE 3.0e10 /* pressure shown in "hottest" color */ +#define PARTIAL_THERMO_COUPLING 0 /* set to 1 to couple only particles to the right of obstacle to thermostat */ +#define PARTIAL_THERMO_REGION 1 /* region for partial thermostat coupling (see list in global_ljones.c) */ +#define PARTIAL_THERMO_SHIFT 0.2 /* distance from obstacle at the right of which particles are coupled to thermostat */ +#define PARTIAL_THERMO_WIDTH 0.5 /* vertical size of partial thermostat coupling */ +#define PARTIAL_THERMO_HEIGHT 0.2 /* vertical size of partial thermostat coupling */ + +#define INCREASE_KREPEL 0 /* set to 1 to increase KREPEL during simulation */ +#define KREPEL_FACTOR 1000.0 /* factor by which to change KREPEL during simulation */ + +#define PART_AT_BOTTOM 0 /* set to 1 to include "seed" particles at bottom */ +#define MASS_PART_BOTTOM 10000.0 /* mass of particles at bottom */ +#define NPART_BOTTOM 100 /* number of particles at the bottom */ + +#define ADD_PARTICLES 0 /* set to 1 to add particles */ +#define ADD_TIME 0 /* time at which to add first particle */ +#define ADD_PERIOD 10000 /* time interval between adding further particles */ +#define FINAL_NOADD_PERIOD 200 /* final period where no particles are added */ +#define SAFETY_FACTOR 2.0 /* no particles are added at distance less than MU*SAFETY_FACTOR of other particles */ + +#define TRACER_PARTICLE 0 /* set to 1 to have a tracer particle */ +#define N_TRACER_PARTICLES 3 /* number of tracer particles */ +#define TRAJECTORY_LENGTH 8000 /* length of recorded trajectory */ +#define TRACER_PARTICLE_MASS 4.0 /* relative mass of tracer particle */ +#define TRAJECTORY_WIDTH 3 /* width of tracer particle trajectory */ + +#define ROTATE_BOUNDARY 0 /* set to 1 to rotate the repelling segments */ +#define SMOOTH_ROTATION 1 /* set to 1 to update segments at each time step (rather than at each movie frame) */ +#define PERIOD_ROTATE_BOUNDARY 1000 /* period of rotating boundary */ +#define ROTATE_INITIAL_TIME 0 /* initial time without rotation */ +#define ROTATE_FINAL_TIME 100 /* final time without rotation */ +#define ROTATE_CHANGE_TIME 0.33 /* relative duration of acceleration/deceleration phases */ +#define OMEGAMAX 100.0 /* maximal rotation speed */ +#define PRINT_OMEGA 0 /* set to 1 to print angular speed */ +#define PRINT_PARTICLE_SPEEDS 0 /* set to 1 to print average speeds/momenta of particles */ +#define PRINT_SEGMENTS_SPEEDS 1 /* set to 1 to print velocity of moving segments */ + +#define MOVE_BOUNDARY 0 /* set to 1 to move repelling segments, due to force from particles */ +#define SEGMENTS_MASS 40.0 /* mass of collection of segments */ +#define DEACTIVATE_SEGMENT 1 /* set to 1 to deactivate last segment after a certain time */ +#define SEGMENT_DEACTIVATION_TIME 200 /* time at which to deactivate last segment */ +#define RELEASE_ROCKET_AT_DEACTIVATION 1 /* set to 1 to limit segments velocity before segment release */ +#define SEGMENTS_X0 1.5 /* initial position of segments */ +#define SEGMENTS_Y0 0.0 /* initial position of segments */ +#define SEGMENTS_VX0 0.0 /* initial velocity of segments */ +#define SEGMENTS_VY0 0.0 /* initial velocity of segments */ +#define DAMP_SEGS_AT_NEGATIVE_Y 0 /* set to 1 to dampen segments when y coordinate is negative */ + +#define MOVE_SEGMENT_GROUPS 1 /* set to 1 to group segments into moving units */ +#define SEGMENT_GROUP_MASS 1000.0 /* mass of segment group */ +#define SEGMENT_GROUP_I 25.0 /* moment of inertia of segment group */ +#define SEGMENT_GROUP_DAMPING 0.0 /* damping of segment groups */ +#define GROUP_REPULSION 1 /* set to 1 for groups of segments to repel each other */ +#define KSPRING_GROUPS 1.0e8 /* harmonic potential between segment groups */ +#define GROUP_WIDTH 0.2 /* interaction width of groups */ +#define GROUP_G_REPEL 1 /* set to 1 to add repulsion between centers of mass of groups */ +#define GROUP_G_REPEL_RADIUS 1.0 /* radius within which centers of mass of groups repel each other */ +#define TRACK_SEGMENT_GROUPS 1 /* set to 1 for view to track group of segments */ +#define TRACK_X_PADDING 2.0 /* distance from x boundary where tracking starts */ + +#define POSITION_DEPENDENT_TYPE 0 /* set to 1 to make particle type depend on initial position */ +#define POSITION_Y_DEPENDENCE 0 /* set to 1 for the separation between particles to be horizontal */ +#define PRINT_ENTROPY 0 /* set to 1 to compute entropy */ + +#define REACTION_DIFFUSION 0 /* set to 1 to simulate a chemical reaction (particles may change type) */ +#define RD_TYPES 3 /* number of types in reaction-diffusion equation */ +#define REACTION_PROB 0.0045 /* probability controlling reaction term */ + +#define PRINT_PARTICLE_NUMBER 0 /* set to 1 to print total number of particles */ +#define PRINT_LEFT 0 /* set to 1 to print certain parameters at the top left instead of right */ +#define PLOT_SPEEDS 1 /* set to 1 to add a plot of obstacle speeds (e.g. for rockets) */ +#define VMAX_PLOT_SPEEDS 0.6 /* vertical scale of plot of obstacle speeds */ + +#define EHRENFEST_COPY 0 /* set to 1 to add equal number of larger particles (for Ehrenfest model) */ + +#define LID_MASS 1000.0 /* mass of lid for BC_RECTANGLE_LID b.c. */ +#define LID_WIDTH 0.1 /* width of lid for BC_RECTANGLE_LID b.c. */ +#define WALL_MASS 2000.0 /* mass of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_FRICTION 0.0 /* friction on wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_WIDTH 0.1 /* width of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_VMAX 100.0 /* max speed of wall */ +#define WALL_TIME 0 /* time during which to keep wall */ + +#define NXMAZE 10 /* width of maze */ +#define NYMAZE 10 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 200 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +#define FLOOR_FORCE 1 /* set to 1 to limit force on particle to FMAX */ +#define FMAX 1.0e12 /* maximal force */ +#define FLOOR_OMEGA 0 /* set to 1 to limit particle momentum to PMAX */ +#define PMAX 1000.0 /* maximal force */ + +#define HASHX 160 /* size of hashgrid in x direction */ +#define HASHY 600 /* size of hashgrid in y direction */ +#define HASHMAX 100 /* maximal number of particles per hashgrid cell */ +#define HASHGRID_PADDING 0.1 /* padding of hashgrid outside simulation window */ + +#define DRAW_COLOR_SCHEME 0 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 8.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 12.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +``` + +### 21 October 22 - Solving a maze with waves: 3D rendering ### + +**Program:** `wave_3d.c` + +**Initial condition in function `animation()`:** `init_circular_wave_mod(-1.5*LAMBDA, 0.5*LAMBDA, phi, psi, xy_in);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 2700 /* number of grid points on x axis */ +#define NY 1350 /* number of grid points on y axis */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +#define HIGHRES 1 /* set to 1 if resolution of grid is double that of displayed image */ + +#define JULIA_SCALE 0.8 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 53 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 2 /* pattern of circles or polygons, see list in global_pdes.c */ + +#define COMPARISON 0 /* set to 1 to compare two different patterns */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ + +#define VARIABLE_IOR 0 /* set to 1 for a variable index of refraction */ +#define IOR 2 /* choice of index of refraction, see list in global_pdes.c */ +#define MANDEL_IOR_SCALE -0.05 /* parameter controlling dependence of IoR on Mandelbrot escape speed */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 1 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 1.0 /* parameter controlling the dimensions of domain */ +#define MU 0.3 /* parameter controlling the dimensions of domain */ +#define NPOLY 3 /* number of sides of polygon */ +#define APOLY 2.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 7 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 12 /* number of grid point for grid of disks */ +#define NGRIDY 16 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -2.9 +#define ISO_XSHIFT_RIGHT 1.4 +#define ISO_YSHIFT_LEFT -0.15 +#define ISO_YSHIFT_RIGHT -0.15 +#define ISO_SCALE 0.5 /* coordinates for isospectral billiards */ + + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard below */ + +/* Physical parameters of wave equation */ + +#define TWOSPEEDS 0 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OSCILLATE_LEFT 0 /* set to 1 to add oscilating boundary condition on the left */ +#define OSCILLATE_TOPBOT 0 /* set to 1 to enforce a planar wave on top and bottom boundary */ +#define OSCILLATION_SCHEDULE 3 /* oscillation schedule, see list in global_pdes.c */ + +#define OMEGA 0.001 /* frequency of periodic excitation */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.2 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COURANT 0.1 /* Courant number */ +#define COURANTB 0.2 /* Courant number in medium B */ +#define GAMMA 0.0 /* damping factor in wave equation */ +#define GAMMAB 0.0075 /* damping factor in wave equation */ +#define GAMMA_SIDES 1.0e-4 /* damping factor on boundary */ +#define GAMMA_TOPBOT 1.0e-7 /* damping factor on boundary */ +#define KAPPA 0.0 /* "elasticity" term enforcing oscillations */ +#define KAPPA_SIDES 5.0e-4 /* "elasticity" term on absorbing boundary */ +#define KAPPA_TOPBOT 0.0 /* "elasticity" term on absorbing boundary */ +/* The Courant number is given by c*DT/DX, where DT is the time step and DX the lattice spacing */ +/* The physical damping coefficient is given by GAMMA/(DT)^2 */ +/* Increasing COURANT speeds up the simulation, but decreases accuracy */ +/* For similar wave forms, COURANT^2*GAMMA should be kept constant */ + +#define ADD_OSCILLATING_SOURCE 0 /* set to 1 to add an oscillating wave source */ +#define OSCILLATING_SOURCE_PERIOD 30 /* period of oscillating source */ + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 2 + +#define PRECOMPUTE_BC 0 /* set to 1 to compute neighbours for Laplacian in advance */ + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 2500 /* number of frames of movie */ +#define NVID 10 /* number of iterations between images displayed on screen */ +#define NSEG 1000 /* number of segments of boundary */ +#define INITIAL_TIME 0 /* time after which to start saving frames */ +#define BOUNDARY_WIDTH 2 /* width of billiard boundary */ +#define PRINT_SPEED 0 /* set to 1 to print speed of moving source */ + +#define PAUSE 100 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 100 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ +#define ROTATE_VIEW_WHILE_FADE 1 /* set to 1 to keep rotating viewpoint during fade */ + +/* Parameters of initial condition */ + +#define INITIAL_AMP 0.75 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.1 /* wavelength of initial condition */ + +/* Plot type, see list in global_pdes.c */ + +#define ZPLOT 103 /* wave height */ +#define CPLOT 103 /* color scheme */ + +#define ZPLOT_B 107 +#define CPLOT_B 107 /* plot type for second movie */ + +#define AMPLITUDE_HIGH_RES 1 /* set to 1 to increase resolution of plot */ +#define SHADE_3D 1 /* set to 1 to change luminosity according to normal vector */ +#define NON_DIRICHLET_BC 0 /* set to 1 to draw only facets in domain, if field is not zero on boundary */ +#define FLOOR_ZCOORD 1 /* set to 1 to draw only facets with z not too negative */ +#define DRAW_BILLIARD 1 /* set to 1 to draw boundary */ +#define DRAW_BILLIARD_FRONT 1 /* set to 1 to draw front of boundary after drawing wave */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw construction lines of certain domains */ +#define FADE_IN_OBSTACLE 1 /* set to 1 to fade color inside obstacles */ +#define DRAW_OUTSIDE_GRAY 0 /* experimental, draw outside of billiard in gray */ + +#define PLOT_SCALE_ENERGY 0.01 /* vertical scaling in energy plot */ +#define PLOT_SCALE_LOG_ENERGY 0.75 /* vertical scaling in log energy plot */ + +/* 3D representation */ + +#define REPRESENTATION_3D 1 /* choice of 3D representation */ + +#define REP_AXO_3D 0 /* linear projection (axonometry) */ +#define REP_PROJ_3D 1 /* projection on plane orthogonal to observer line of sight */ + +#define ROTATE_VIEW 0 /* set to 1 to rotate position of observer */ +#define ROTATE_ANGLE 360.0 /* total angle of rotation during simulation */ + +/* Color schemes */ + +#define COLOR_PALETTE 15 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 13 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_pdes.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define VSCALE_AMPLITUDE 1.0 /* additional scaling factor for color scheme P_3D_AMPLITUDE */ +#define VSCALE_ENERGY 200.0 /* additional scaling factor for color scheme P_3D_ENERGY */ +#define PHASE_FACTOR 20.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define E_SCALE 1000.0 /* scaling factor for energy representation */ +#define LOG_SCALE 1.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT 0.25 /* shift of colors on log scale */ +#define LOG_ENERGY_FLOOR -20.0 /* floor value for log of (total) energy */ +#define LOG_MEAN_ENERGY_SHIFT 1.0 /* additional shift for log of mean energy */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 240.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -200.0 /* amplitude of variation of hue for color scheme C_HUE */ + +#define NXMAZE 7 /* width of maze */ +#define NYMAZE 7 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 24 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 2.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 15.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +#define SAVE_TIME_SERIES 0 /* set to 1 to save wave time series at a point */ + +/* For debugging purposes only */ +#define FLOOR 1 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ + +/* Parameters controlling 3D projection */ + +double u_3d[2] = {0.75, -0.45}; /* projections of basis vectors for REP_AXO_3D representation */ +double v_3d[2] = {-0.75, -0.45}; +double w_3d[2] = {0.0, 0.015}; +double light[3] = {0.816496581, -0.40824829, 0.40824829}; /* vector of "light" direction for P_3D_ANGLE color scheme */ +double observer[3] = {8.0, 8.0, 6.0}; /* location of observer for REP_PROJ_3D representation */ +int reset_view = 0; /* switch to reset 3D view parameters (for option ROTATE_VIEW) */ + +#define Z_SCALING_FACTOR 0.1 /* overall scaling factor of z axis for REP_PROJ_3D representation */ +#define XY_SCALING_FACTOR 2.1 /* overall scaling factor for on-screen (x,y) coordinates after projection */ +#define ZMAX_FACTOR 1.0 /* max value of z coordinate for REP_PROJ_3D representation */ +#define XSHIFT_3D 0.0 /* overall x shift for REP_PROJ_3D representation */ +#define YSHIFT_3D 0.1 /* overall y shift for REP_PROJ_3D representation */ + +``` + +### 20 October 22 - Shining a laser beam into a mirrored maze: High fps version without slowdown ### + +**Program:** `particle_trajectory.c` + +**In function `animation()`:** +``` + time = (double)i/(double)(NSTEPS-1); + x = -1.65; + y = 0.22; + alpha = angle_schedule(time); +``` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define SCALING_FACTOR 1.0 /* scaling factor of drawing, needed for flower billiards, otherwise set to 1.0 */ + +/* Choice of the billiard table, see global_particles.c */ + +#define B_DOMAIN 30 /* choice of domain shape */ + +#define CIRCLE_PATTERN 6 /* pattern of circles */ +#define POLYLINE_PATTERN 10 /* pattern of polyline */ + +#define ABSORBING_CIRCLES 1 /* set to 1 for circular scatterers to be absorbing */ + +#define NMAXCIRCLES 50000 /* total number of circles (must be at least NCX*NCY for square grid) */ +#define NMAXPOLY 50000 /* total number of sides of polygonal line */ +#define NCX 9 /* number of circles in x direction */ +#define NCY 20 /* number of circles in y direction */ +#define NPOISSON 500 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define NGOLDENSPIRAL 2000 /* max number of points for C_GOLDEN_SPIRAL arrandement */ +#define SDEPTH 2 /* Sierpinski gastket depth */ + +#define LAMBDA -1.1 /* parameter controlling shape of domain */ +#define MU 0.1 /* second parameter controlling shape of billiard */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NPOLY 3 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define DRAW_BILLIARD 1 /* set to 1 to draw billiard */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw additional construction lines for billiard */ +#define PERIODIC_BC 0 /* set to 1 to enforce periodic boundary conditions when drawing particles */ +#define PENROSE_RATIO 2.5 /* parameter controlling the shape of small ellipses in Penrose room */ + +#define RESAMPLE 0 /* set to 1 if particles should be added when dispersion too large */ +#define DEBUG 0 /* draw trajectories, for debugging purposes */ + +/* Simulation parameters */ + +#define NPART 1 /* number of particles */ +#define NPARTMAX 100000 /* maximal number of particles after resampling */ +#define TRAJ_LENGTH 10000 /* length of trajectory */ +#define LMAX 0.01 /* minimal segment length triggering resampling */ +#define DMIN 0.02 /* minimal distance to boundary for triggering resampling */ +#define CYCLE 1 /* set to 1 for closed curve (start in all directions) */ +#define SHOWTRAILS 0 /* set to 1 to keep trails of the particles */ +#define SHOWZOOM 0 /* set to 1 to show zoom on specific area */ +#define TEST_ACTIVE 1 /* set to 1 to test whether particle is in billiard */ +#define PRINT_TRAJECTORY_LENGTH 1 /* set to 1 to print length of trajectory 0 */ +#define PRINT_TRAJECTORY_ANGLE 1 /* set to 1 to print angle of trajectory 0 */ +#define PRINT_TRAJECTORY_PERIOD 0 /* set to 1 to print period of trajectory 0 */ +#define DRAW_LENGTHS_PLOT 1 /* set to 1 to plot trajectory lengths */ +#define LENGTHS_LOG_SCALE 1 /* set to 1 to use log scale for plot of lengths */ +#define MAX_ANGLE 45.0 /* range of angles of trajectory */ +#define TEST_INITIAL_COND 1 /* set to 1 to allow only initial conditions that pass a test */ + +#define SLOW_AT_LONG_TRAJ 0 /* set to 1 to slow down movie for long trajectories */ +#define ADD_SUCCESS_GALLERY 1 /* set to 1 to add gallery of successful trajectories at end of movie */ +#define SUCCESS_GALLERY_FRAMES 50 /* number of frames per success */ + +#define NSTEPS 7000 /* number of frames of movie */ +#define TIME 2500 /* time between movie frames, for fluidity of real-time simulation */ +#define DPHI 0.00001 /* integration step */ +#define NVID 150 /* number of iterations between images displayed on screen */ + +/* Decreasing TIME accelerates the animation and the movie */ +/* For constant speed of movie, TIME*DPHI should be kept constant */ +/* However, increasing DPHI too much deterioriates quality of simulation */ +/* NVID tells how often a picture is drawn in the animation, increase it for faster anim */ +/* For a good quality movie, take for instance TIME = 400, DPHI = 0.00005, NVID = 100 */ + +/* Colors and other graphical parameters */ + +#define COLOR_PALETTE 11 /* Color palette, see list in global_pdes.c */ + +#define NCOLORS 64 /* number of colors */ +#define COLORSHIFT 0 /* hue of initial color */ +#define RAINBOW_COLOR 0 /* set to 1 to use different colors for all particles */ +#define FLOWER_COLOR 0 /* set to 1 to adapt initial colors to flower billiard (tracks vs core) */ +#define NSEG 100 /* number of segments of boundary */ +#define LENGTH 0.03 /* length of velocity vectors */ +#define BILLIARD_WIDTH 2 /* width of billiard */ +#define PARTICLE_WIDTH 2 /* width of particles */ +#define FRONT_WIDTH 3 /* width of wave front */ + +#define BLACK 1 /* set to 1 for black background */ +#define COLOR_OUTSIDE 0 /* set to 1 for colored outside */ +#define OUTER_COLOR 270.0 /* color outside billiard */ +#define PAINT_INT 0 /* set to 1 to paint interior in other color (for polygon/Reuleaux) */ +#define PAINT_EXT 1 /* set to 1 to paint exterior */ + +#define PAUSE 500 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define END_FRAMES 100 /* number of frames at end of movie */ + +#define NXMAZE 8 /* width of maze */ +#define NYMAZE 8 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 58 /* seed of random number generator */ +#define MAZE_XSHIFT -0.5 /* horizontal shift of maze */ + +``` + +### 19 October 22 - Tracking a rocket able to rotate ### + +**Program:** `lennardjones.c` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 0 /* set to 1 to produce movies for wave height and energy simultaneously */ + +#define TIME_LAPSE 1 /* set to 1 to add a time-lapse movie at the end */ + /* so far incompatible with double movie */ +#define TIME_LAPSE_FACTOR 3 /* factor of time-lapse movie */ +#define TIME_LAPSE_FIRST 1 /* set to 1 to show time-lapse version first */ + +/* General geometrical parameters */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -3.3 +#define XMAX 4.7 /* x interval */ +#define YMIN -2.25 +#define YMAX 2.25 /* y interval for 9/16 aspect ratio */ + +#define INITXMIN -0.7 +#define INITXMAX 0.7 /* x interval for initial condition */ +#define INITYMIN -1.7 +#define INITYMAX 2.5 /* y interval for initial condition */ + +#define BCXMIN -5.1 +#define BCXMAX 6.1 /* x interval for boundary condition */ +#define BCYMIN -6.5 +#define BCYMAX 44.0 /* y interval for boundary condition */ + +#define OBSXMIN -2.0 +#define OBSXMAX 2.0 /* x interval for motion of obstacle */ + +#define CIRCLE_PATTERN 8 /* pattern of circles, see list in global_ljones.c */ + +#define ADD_FIXED_OBSTACLES 0 /* set to 1 do add fixed circular obstacles */ +#define OBSTACLE_PATTERN 3 /* pattern of obstacles, see list in global_ljones.c */ + +#define ADD_FIXED_SEGMENTS 1 /* set to 1 to add fixed segments as obstacles */ +#define SEGMENT_PATTERN 101 /* pattern of repelling segments, see list in global_ljones.c */ +#define ROCKET_SHAPE 1 /* shape of rocket combustion chamber, see list in global_ljones.c */ +#define ROCKET_SHAPE_B 0 /* shape of second rocket */ +#define NOZZLE_SHAPE 1 /* shape of nozzle, see list in global_ljones.c */ +#define NOZZLE_SHAPE_B 4 /* shape of nozzle for second rocket, see list in global_ljones.c */ + +#define TWO_TYPES 0 /* set to 1 to have two types of particles */ +#define TPYE_PROPORTION 0.5 /* proportion of particles of first type */ +#define SYMMETRIZE_FORCE 1 /* set to 1 to symmetrize two-particle interaction, only needed if particles are not all the same */ +#define CENTER_PX 0 /* set to 1 to center horizontal momentum */ +#define CENTER_PY 0 /* set to 1 to center vertical momentum */ +#define CENTER_PANGLE 0 /* set to 1 to center angular momentum */ + +#define INTERACTION 1 /* particle interaction, see list in global_ljones.c */ +#define INTERACTION_B 1 /* particle interaction for second type of particle, see list in global_ljones.c */ +#define SPIN_INTER_FREQUENCY 5.0 /* angular frequency of spin-spin interaction */ +#define SPIN_INTER_FREQUENCY_B 2.0 /* angular frequency of spin-spin interaction for second particle type */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 100 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define PDISC_DISTANCE 2.5 /* minimal distance in Poisson disc process, controls density of particles */ +#define PDISC_CANDIDATES 100 /* number of candidates in construction of Poisson disc process */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.8 /* parameter controlling the dimensions of domain */ +#define MU 0.007 /* parameter controlling radius of particles */ +#define MU_B 0.018 /* parameter controlling radius of particles of second type */ +#define NPOLY 25 /* number of sides of polygon */ +#define APOLY 0.666666666 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 4 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 90 /* number of grid point for grid of disks */ +#define NGRIDY 100 /* number of grid point for grid of disks */ +#define EHRENFEST_RADIUS 0.9 /* radius of container for Ehrenfest urn configuration */ +#define EHRENFEST_WIDTH 0.035 /* width of tube for Ehrenfest urn configuration */ +#define TWO_CIRCLES_RADIUS_RATIO 0.8 /* ratio of radii for S_TWO_CIRCLES_EXT segment configuration */ +#define DAM_WIDTH 0.05 /* width of dam for S_DAM segment configuration */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 2750 /* number of frames of movie */ +#define NVID 100 /* number of iterations between images displayed on screen */ +#define NSEG 250 /* number of segments of boundary */ +#define INITIAL_TIME 10 /* time after which to start saving frames */ +#define OBSTACLE_INITIAL_TIME 200 /* time after which to start moving obstacle */ +#define BOUNDARY_WIDTH 1 /* width of particle boundary */ +#define LINK_WIDTH 2 /* width of links between particles */ +#define CONTAINER_WIDTH 4 /* width of container boundary */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ + +/* Boundary conditions, see list in global_ljones.c */ + +#define BOUNDARY_COND 20 + +/* Plot type, see list in global_ljones.c */ + +#define PLOT 0 +#define PLOT_B 8 /* plot type for second movie */ + +#define DRAW_BONDS 0 /* set to 1 to draw bonds between neighbours */ +#define COLOR_BONDS 1 /* set to 1 to color bonds according to length */ +#define FILL_TRIANGLES 1 /* set to 1 to fill triangles between neighbours */ + +/* Color schemes */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_ljones.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_ljones.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 0.5 /* sensitivity of color on wave amplitude */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 220.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -50.0 /* amplitude of variation of hue for color scheme C_HUE */ + +/* particle properties */ + +#define ENERGY_HUE_MIN 330.0 /* color of original particle */ +#define ENERGY_HUE_MAX 50.0 /* color of saturated particle */ +#define PARTICLE_HUE_MIN 359.0 /* color of original particle */ +#define PARTICLE_HUE_MAX 0.0 /* color of saturated particle */ +#define PARTICLE_EMAX 2.0e2 /* energy of particle with hottest color */ +#define HUE_TYPE0 70.0 /* hue of particles of type 0 */ +#define HUE_TYPE1 280.0 /* hue of particles of type 1 */ +#define HUE_TYPE2 .0 /* hue of particles of type 2 */ +#define HUE_TYPE3 210.0 /* hue of particles of type 3 */ + +#define RANDOM_RADIUS 0 /* set to 1 for random circle radius */ +#define DT_PARTICLE 3.0e-6 /* time step for particle displacement */ +#define KREPEL 12.0 /* constant in repelling force between particles */ +#define EQUILIBRIUM_DIST 4.5 /* Lennard-Jones equilibrium distance */ +#define EQUILIBRIUM_DIST_B 3.5 /* Lennard-Jones equilibrium distance for second type of particle */ +#define REPEL_RADIUS 20.0 /* radius in which repelling force acts (in units of particle radius) */ +#define DAMPING 5.0 /* damping coefficient of particles */ +#define PARTICLE_MASS 1.0 /* mass of particle of radius MU */ +#define PARTICLE_MASS_B 1.0 /* mass of particle of radius MU */ +#define PARTICLE_INERTIA_MOMENT 0.2 /* moment of inertia of particle */ +#define PARTICLE_INERTIA_MOMENT_B 0.02 /* moment of inertia of second type of particle */ +#define V_INITIAL 0.0 /* initial velocity range */ +#define OMEGA_INITIAL 10.0 /* initial angular velocity range */ + +#define THERMOSTAT 1 /* set to 1 to switch on thermostat */ +#define VARY_THERMOSTAT 0 /* set to 1 for time-dependent thermostat schedule */ +#define SIGMA 5.0 /* noise intensity in thermostat */ +#define BETA 0.02 /* initial inverse temperature */ +#define MU_XI 0.01 /* friction constant in thermostat */ +#define KSPRING_BOUNDARY 1.0e7 /* confining harmonic potential outside simulation region */ +#define KSPRING_OBSTACLE 1.0e11 /* harmonic potential of obstacles */ +#define NBH_DIST_FACTOR 7.5 /* radius in which to count neighbours */ +#define GRAVITY 15.0 /* gravity acting on all particles */ +#define GRAVITY_X 0.0 /* horizontal gravity acting on all particles */ +#define INCREASE_GRAVITY 0 /* set to 1 to increase gravity during the simulation */ +#define GRAVITY_SCHEDULE 2 /* type of gravity schedule, see list in global_ljones.c */ +#define GRAVITY_FACTOR 100.0 /* factor by which to increase gravity */ +#define GRAVITY_INITIAL_TIME 200 /* time at start of simulation with constant gravity */ +#define GRAVITY_RESTORE_TIME 700 /* time at end of simulation with gravity restored to initial value */ + +#define ROTATION 0 /* set to 1 to include rotation of particles */ +#define COUPLE_ANGLE_TO_THERMOSTAT 0 /* set to 1 to couple angular degrees of freedom to thermostat */ +#define DIMENSION_FACTOR 1.0 /* scaling factor taking into account number of degrees of freedom */ +#define KTORQUE 100.0 /* force constant in angular dynamics */ +#define KTORQUE_B 10.0 /* force constant in angular dynamics */ +#define KTORQUE_DIFF 150.0 /* force constant in angular dynamics for different particles */ +#define DRAW_SPIN 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_SPIN_B 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_CROSS 1 /* set to 1 to draw cross on particles of second type */ +#define SPIN_RANGE 7.0 /* range of spin-spin interaction */ +#define SPIN_RANGE_B 5.0 /* range of spin-spin interaction for second type of particle */ +#define QUADRUPOLE_RATIO 0.6 /* anisotropy in quadrupole potential */ + +#define INCREASE_BETA 1 /* set to 1 to increase BETA during simulation */ +#define BETA_FACTOR 0.025 /* factor by which to change BETA during simulation */ +#define N_TOSCILLATIONS 1.5 /* number of temperature oscillations in BETA schedule */ +#define NO_OSCILLATION 1 /* set to 1 to have exponential BETA change only */ +#define MIDDLE_CONSTANT_PHASE 1050 /* final phase in which temperature is constant */ +#define FINAL_DECREASE_PHASE 1500 /* final phase in which temperature decreases */ +#define FINAL_CONSTANT_PHASE -1 /* final phase in which temperature is constant */ + +#define DECREASE_CONTAINER_SIZE 0 /* set to 1 to decrease size of container */ +#define SYMMETRIC_DECREASE 0 /* set tp 1 to decrease container symmetrically */ +#define COMPRESSION_RATIO 0.3 /* final size of container */ +#define RESTORE_CONTAINER_SIZE 1 /* set to 1 to restore container to initial size at end of simulation */ +#define RESTORE_TIME 700 /* time before end of sim at which to restore size */ + +#define MOVE_OBSTACLE 0 /* set to 1 to have a moving obstacle */ +#define CENTER_VIEW_ON_OBSTACLE 0 /* set to 1 to center display on moving obstacle */ +#define RESAMPLE_Y 0 /* set to 1 to resample y coordinate of moved particles (for shock waves) */ +#define NTRIALS 2000 /* number of trials when resampling */ +#define OBSTACLE_RADIUS 0.12 /* radius of obstacle for circle boundary conditions */ +#define FUNNEL_WIDTH 0.25 /* funnel width for funnel boundary conditions */ +#define OBSTACLE_XMIN 0.0 /* initial position of obstacle */ +#define OBSTACLE_XMAX 3.0 /* final position of obstacle */ +#define RECORD_PRESSURES 0 /* set to 1 to record pressures on obstacle */ +#define N_PRESSURES 100 /* number of intervals to record pressure */ +#define N_P_AVERAGE 100 /* size of pressure averaging window */ +#define N_T_AVERAGE 50 /* size of temperature averaging window */ +#define MAX_PRESSURE 3.0e10 /* pressure shown in "hottest" color */ +#define PARTIAL_THERMO_COUPLING 0 /* set to 1 to couple only particles to the right of obstacle to thermostat */ +#define PARTIAL_THERMO_REGION 1 /* region for partial thermostat coupling (see list in global_ljones.c) */ +#define PARTIAL_THERMO_SHIFT 0.2 /* distance from obstacle at the right of which particles are coupled to thermostat */ +#define PARTIAL_THERMO_WIDTH 0.5 /* vertical size of partial thermostat coupling */ +#define PARTIAL_THERMO_HEIGHT 0.2 /* vertical size of partial thermostat coupling */ + +#define INCREASE_KREPEL 0 /* set to 1 to increase KREPEL during simulation */ +#define KREPEL_FACTOR 1000.0 /* factor by which to change KREPEL during simulation */ + +#define PART_AT_BOTTOM 0 /* set to 1 to include "seed" particles at bottom */ +#define MASS_PART_BOTTOM 10000.0 /* mass of particles at bottom */ +#define NPART_BOTTOM 100 /* number of particles at the bottom */ + +#define ADD_PARTICLES 0 /* set to 1 to add particles */ +#define ADD_TIME 0 /* time at which to add first particle */ +#define ADD_PERIOD 10000 /* time interval between adding further particles */ +#define FINAL_NOADD_PERIOD 200 /* final period where no particles are added */ +#define SAFETY_FACTOR 2.0 /* no particles are added at distance less than MU*SAFETY_FACTOR of other particles */ + +#define TRACER_PARTICLE 0 /* set to 1 to have a tracer particle */ +#define N_TRACER_PARTICLES 3 /* number of tracer particles */ +#define TRAJECTORY_LENGTH 8000 /* length of recorded trajectory */ +#define TRACER_PARTICLE_MASS 4.0 /* relative mass of tracer particle */ +#define TRAJECTORY_WIDTH 3 /* width of tracer particle trajectory */ + +#define ROTATE_BOUNDARY 0 /* set to 1 to rotate the repelling segments */ +#define SMOOTH_ROTATION 1 /* set to 1 to update segments at each time step (rather than at each movie frame) */ +#define PERIOD_ROTATE_BOUNDARY 1000 /* period of rotating boundary */ +#define ROTATE_INITIAL_TIME 0 /* initial time without rotation */ +#define ROTATE_FINAL_TIME 100 /* final time without rotation */ +#define ROTATE_CHANGE_TIME 0.33 /* relative duration of acceleration/deceleration phases */ +#define OMEGAMAX 100.0 /* maximal rotation speed */ +#define PRINT_OMEGA 0 /* set to 1 to print angular speed */ +#define PRINT_PARTICLE_SPEEDS 0 /* set to 1 to print average speeds/momenta of particles */ +#define PRINT_SEGMENTS_SPEEDS 1 /* set to 1 to print velocity of moving segments */ + +#define MOVE_BOUNDARY 0 /* set to 1 to move repelling segments, due to force from particles */ +#define SEGMENTS_MASS 40.0 /* mass of collection of segments */ +#define DEACTIVATE_SEGMENT 1 /* set to 1 to deactivate last segment after a certain time */ +#define SEGMENT_DEACTIVATION_TIME 200 /* time at which to deactivate last segment */ +#define RELEASE_ROCKET_AT_DEACTIVATION 1 /* set to 1 to limit segments velocity before segment release */ +#define SEGMENTS_X0 0.0 /* initial position of segments */ +#define SEGMENTS_Y0 0.0 /* initial position of segments */ +#define SEGMENTS_VX0 0.0 /* initial velocity of segments */ +#define SEGMENTS_VY0 0.0 /* initial velocity of segments */ +#define DAMP_SEGS_AT_NEGATIVE_Y 0 /* set to 1 to dampen segments when y coordinate is negative */ + +#define MOVE_SEGMENT_GROUPS 1 /* set to 1 to group segments into moving units */ +#define SEGMENT_GROUP_MASS 1000.0 /* mass of segment group */ +#define SEGMENT_GROUP_I 25.0 /* moment of inertia of segment group */ +#define SEGMENT_GROUP_DAMPING 0.0 /* damping of segment groups */ +#define GROUP_REPULSION 0 /* set to 1 for groups of segments to repel each other */ +#define KSPRING_GROUPS 1.0e8 /* harmonic potential between segment groups */ +#define GROUP_WIDTH 0.05 /* interaction width of groups */ +#define GROUP_G_REPEL 0 /* set to 1 to add repulsion between centers of mass of groups */ +#define GROUP_G_REPEL_RADIUS 0.12 /* radius within which centers of mass of groups repel each other */ +#define TRACK_SEGMENT_GROUPS 1 /* set to 1 for view to track group of segments */ +#define TRACK_X_PADDING 1.2 /* distance from x boundary where tracking starts */ + +#define POSITION_DEPENDENT_TYPE 0 /* set to 1 to make particle type depend on initial position */ +#define POSITION_Y_DEPENDENCE 0 /* set to 1 for the separation between particles to be horizontal */ +#define PRINT_ENTROPY 0 /* set to 1 to compute entropy */ + +#define REACTION_DIFFUSION 0 /* set to 1 to simulate a chemical reaction (particles may change type) */ +#define RD_TYPES 3 /* number of types in reaction-diffusion equation */ +#define REACTION_PROB 0.0045 /* probability controlling reaction term */ + +#define PRINT_PARTICLE_NUMBER 0 /* set to 1 to print total number of particles */ +#define PRINT_LEFT 1 /* set to 1 to print certain parameters at the top left instead of right */ +#define PLOT_SPEEDS 1 /* set to 1 to add a plot of obstacle speeds (e.g. for rockets) */ +#define VMAX_PLOT_SPEEDS 0.6 /* vertical scale of plot of obstacle speeds */ + +#define EHRENFEST_COPY 0 /* set to 1 to add equal number of larger particles (for Ehrenfest model) */ + +#define LID_MASS 1000.0 /* mass of lid for BC_RECTANGLE_LID b.c. */ +#define LID_WIDTH 0.1 /* width of lid for BC_RECTANGLE_LID b.c. */ +#define WALL_MASS 2000.0 /* mass of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_FRICTION 0.0 /* friction on wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_WIDTH 0.1 /* width of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_VMAX 100.0 /* max speed of wall */ +#define WALL_TIME 0 /* time during which to keep wall */ + +#define NXMAZE 10 /* width of maze */ +#define NYMAZE 10 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 200 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +#define FLOOR_FORCE 1 /* set to 1 to limit force on particle to FMAX */ +#define FMAX 1.0e12 /* maximal force */ +#define FLOOR_OMEGA 0 /* set to 1 to limit particle momentum to PMAX */ +#define PMAX 1000.0 /* maximal force */ + +#define HASHX 160 /* size of hashgrid in x direction */ +#define HASHY 600 /* size of hashgrid in y direction */ +#define HASHMAX 100 /* maximal number of particles per hashgrid cell */ +#define HASHGRID_PADDING 0.1 /* padding of hashgrid outside simulation window */ + +#define DRAW_COLOR_SCHEME 0 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 8.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 12.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +``` + +### 18 October 22 - A circular wave starting off center in a hexagon-bestagon ### + +**Program:** `wave_billiard.c` + +**Initial condition in function `animation()`:** `init_circular_wave(0.1, 0.1, phi, psi, xy_in);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 3840 /* number of grid points on x axis */ +#define NY 2000 /* number of grid points on y axis */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +#define HIGHRES 1 /* set to 1 if resolution of grid is double that of displayed image */ + +#define JULIA_SCALE 1.0 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 8 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 1 /* pattern of circles or polygons, see list in global_pdes.c */ + +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 1 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 1.0 /* parameter controlling the dimensions of domain */ +#define MU 0.3 /* parameter controlling the dimensions of domain */ +#define NPOLY 6 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 6 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 12 /* number of grid point for grid of disks */ +#define NGRIDY 15 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -2.9 +#define ISO_XSHIFT_RIGHT 1.4 +#define ISO_YSHIFT_LEFT -0.15 +#define ISO_YSHIFT_RIGHT -0.15 +#define ISO_SCALE 0.5 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard below */ + +/* Physical parameters of wave equation */ + +#define TWOSPEEDS 1 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OSCILLATE_LEFT 0 /* set to 1 to add oscilating boundary condition on the left */ +#define OSCILLATE_TOPBOT 0 /* set to 1 to enforce a planar wave on top and bottom boundary */ +#define OSCILLATION_SCHEDULE 1 /* oscillation schedule, see list in global_pdes.c */ + +#define OMEGA 0.0005 /* frequency of periodic excitation */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.25 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COURANT 0.06 /* Courant number */ +#define COURANTB 0.12 /* Courant number in medium B */ +#define GAMMA 0.0 /* damping factor in wave equation */ +#define GAMMAB 0.0 /* damping factor in wave equation */ +#define GAMMA_SIDES 1.0e-4 /* damping factor on boundary */ +#define GAMMA_TOPBOT 1.0e-7 /* damping factor on boundary */ +#define KAPPA 0.0 /* "elasticity" term enforcing oscillations */ +#define KAPPA_SIDES 5.0e-4 /* "elasticity" term on absorbing boundary */ +#define KAPPA_TOPBOT 0.0 /* "elasticity" term on absorbing boundary */ +/* The Courant number is given by c*DT/DX, where DT is the time step and DX the lattice spacing */ +/* The physical damping coefficient is given by GAMMA/(DT)^2 */ +/* Increasing COURANT speeds up the simulation, but decreases accuracy */ +/* For similar wave forms, COURANT^2*GAMMA should be kept constant */ + +#define ADD_OSCILLATING_SOURCE 0 /* set to 1 to add an oscillating wave source */ +#define OSCILLATING_SOURCE_PERIOD 25 /* period of oscillating source */ + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 2 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 3400 /* number of frames of movie */ +#define NVID 20 /* number of iterations between images displayed on screen */ +#define NSEG 1000 /* number of segments of boundary */ +#define INITIAL_TIME 0 /* time after which to start saving frames */ +#define BOUNDARY_WIDTH 2 /* width of billiard boundary */ +#define PRINT_SPEED 0 /* print speed of moving source */ + +#define PAUSE 200 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Parameters of initial condition */ + +#define INITIAL_AMP 0.75 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.01 /* wavelength of initial condition */ + +/* Plot type, see list in global_pdes.c */ + +#define PLOT 0 + +#define PLOT_B 5 /* plot type for second movie */ + +/* Color schemes */ + +#define COLOR_PALETTE 15 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 12 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_pdes.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define PHASE_FACTOR 1.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define E_SCALE 125.0 /* scaling factor for energy representation */ +#define LOG_SCALE 1.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 /* shift of colors on log scale */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 180.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -180.0 /* amplitude of variation of hue for color scheme C_HUE */ + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 2.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 1.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +#define SAVE_TIME_SERIES 0 /* set to 1 to save wave time series at a point */ + +#define NXMAZE 7 /* width of maze */ +#define NYMAZE 7 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 24 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +/* For debugging purposes only */ +#define FLOOR 0 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ + +``` + +### 17 October 22 - Two vortices in the incompressible Euler equation (short version) ### + +**Program:** `rde.c` + +**Initial condition in function `animation()`:** + +``` + init_vortex_state(0.4, 0.0, 0.1, phi, xy_in); + add_vortex_state(-0.4, 0.0, 0.1, phi, xy_in); +``` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 0 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 900 /* window width */ +#define WINHEIGHT 900 /* window height */ +#define NX 450 /* number of grid points on x axis */ +#define NY 450 /* number of grid points on y axis */ + +#define XMIN -1.0 +#define XMAX 1.0 /* x interval */ +#define YMIN -1.0 +#define YMAX 1.0 /* y interval for 9/16 aspect ratio */ + +/* Choice of simulated equation */ + +#define RDE_EQUATION 6 /* choice of reaction term, see list in global_3d.c */ +#define NFIELDS 2 /* number of fields in reaction-diffusion equation */ +#define NLAPLACIANS 1 /* number of fields for which to compute Laplacian */ + +#define ADD_POTENTIAL 0 /* set to 1 to add a potential (for Schrodinger equation) */ +#define ADD_MAGNETIC_FIELD 0 /* set to 1 to add a magnetic field (for Schrodinger equation) - then set POTENTIAL 1 */ +#define POTENTIAL 101 /* type of potential or vector potential, see list in global_3d.c */ + +#define ANTISYMMETRIZE_WAVE_FCT 0 /* set tot 1 to make wave function antisymmetric */ + +#define JULIA_SCALE 0.5 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 999 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 99 /* pattern of circles, see list in global_pdes.c */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 1.0 /* parameter controlling the dimensions of domain */ +#define MU 1.0 /* parameter controlling the dimensions of domain */ +#define NPOLY 5 /* number of sides of polygon */ +#define APOLY 2.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 7 /* depth of computation of Menger gasket */ +#define MRATIO 5 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 15 /* number of grid point for grid of disks */ +#define NGRIDY 20 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -1.65 +#define ISO_XSHIFT_RIGHT 0.4 +#define ISO_YSHIFT_LEFT -0.05 +#define ISO_YSHIFT_RIGHT -0.05 +#define ISO_SCALE 0.85 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard in sub_wave.c */ + +/* Physical patameters of wave equation */ + +#define DT 0.0000012 + +#define VISCOSITY 2.0 + +#define RPSA 0.75 /* parameter in Rock-Paper-Scissors-type interaction */ +#define RPSLZB 0.75 /* second parameter in Rock-Paper-Scissors-Lizard-Spock type interaction */ + +#define EPSILON 0.8 /* time scale separation */ +#define DELTA 0.1 /* time scale separation */ +#define FHNA 1.0 /* parameter in FHN equation */ +#define FHNC -0.01 /* parameter in FHN equation */ +#define K_HARMONIC 1.0 /* spring constant of harmonic potential */ +#define K_COULOMB 0.5 /* constant in Coulomb potential */ +#define BZQ 0.0008 /* parameter in BZ equation */ +#define BZF 1.2 /* parameter in BZ equation */ +#define B_FIELD 10.0 /* magnetic field */ +#define AB_RADIUS 0.2 /* radius of region with magnetic field for Aharonov-Bohm effect */ +#define K_EULER 50.0 /* constant in stream function integration of Euler equation */ + +#define SMOOTHEN_VORTICITY 1 /* set to 1 to smoothen vorticity field in Euler equation */ +#define SMOOTHEN_PERIOD 12 /* period between smoothenings */ +#define SMOOTH_FACTOR 0.01 /* factor by which to smoothen */ + +#define T_OUT 2.0 /* outside temperature */ +#define T_IN 0.0 /* inside temperature */ +#define SPEED 0.0 /* speed of drift to the right */ + +#define ADD_NOISE 0 /* set to 1 to add noise, set to 2 to add noise in right half */ +#define NOISE_INTENSITY 0.005 /* noise intensity */ +#define CHANGE_NOISE 1 /* set to 1 to increase noise intensity */ +#define NOISE_FACTOR 40.0 /* factor by which to increase noise intensity */ +#define NOISE_INITIAL_TIME 100 /* initial time during which noise remains constant */ + +#define CHANGE_VISCOSITY 0 /* set to 1 to change the viscosity in the course of the simulation */ +#define ADJUST_INTSTEP 0 /* set to 1 to decrease integration step when viscosity increases */ +#define VISCOSITY_INITIAL_TIME 10 /* initial time during which viscosity remains constant */ +#define VISCOSITY_FACTOR 100.0 /* factor by which to change viscosity */ +#define VISCOSITY_MAX 2.0 /* max value of viscosity beyond which NVID is increased and integration step is decrase, + for numerical stability */ + +#define CHANGE_RPSLZB 0 /* set to 1 to change second parameter in Rock-Paper-Scissors-Lizard-Spock equation */ +#define RPSLZB_CHANGE 0.75 /* factor by which to rpslzb parameter */ +#define RPSLZB_INITIAL_TIME 0 /* initial time during which rpslzb remains constant */ +#define RPSLZB_FINAL_TIME 500 /* final time during which rpslzb remains constant */ + + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 1 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 1200 /* number of frames of movie */ +#define NVID 350 /* number of iterations between images displayed on screen */ +#define ACCELERATION_FACTOR 1.0 /* factor by which to increase NVID in course of simulation */ +#define DT_ACCELERATION_FACTOR 1.0 /* factor by which to increase time step in course of simulation */ +#define MAX_DT 0.024 /* maximal value of integration step */ +#define NSEG 100 /* number of segments of boundary */ +#define BOUNDARY_WIDTH 5 /* width of billiard boundary */ + +#define PAUSE 100 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 2 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define INITIAL_TIME 0 /* initial still time */ +#define MID_FRAMES 50 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 50 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Visualisation */ + +#define PLOT_3D 0 /* controls whether plot is 2D or 3D */ + +#define ROTATE_VIEW 0 /* set to 1 to rotate position of observer */ +#define ROTATE_ANGLE 360.0 /* total angle of rotation during simulation */ + +/* Plot type - color scheme */ + +#define CPLOT 50 +#define CPLOT_B 51 + +/* Plot type - height of 3D plot */ + +#define ZPLOT 50 /* z coordinate in 3D plot */ +#define ZPLOT_B 51 /* z coordinate in second 3D plot */ + +#define AMPLITUDE_HIGH_RES 1 /* set to 1 to increase resolution of P_3D_AMPLITUDE plot */ +#define SHADE_3D 1 /* set to 1 to change luminosity according to normal vector */ +#define NON_DIRICHLET_BC 0 /* set to 1 to draw only facets in domain, if field is not zero on boundary */ +#define WRAP_ANGLE 1 /* experimental: wrap angle to [0, 2Pi) for interpolation in angle schemes */ +#define FADE_IN_OBSTACLE 0 /* set to 1 to fade color inside obstacles */ +#define DRAW_OUTSIDE_GRAY 0 /* experimental - draw outside of billiard in gray */ +#define ADD_POTENTIAL_TO_Z 1 /* set to 1 to add the external potential to z-coordinate of plot */ +#define ADD_POT_CONSTANT 0.5 /* constant in front of added potential */ + +#define PLOT_SCALE_ENERGY 0.05 /* vertical scaling in energy plot */ + +#define PRINT_TIME 0 /* set to 1 to print running time */ +#define PRINT_VISCOSITY 0 /* set to 1 to print viscosity */ +#define PRINT_RPSLZB 0 /* set to 1 to print rpslzb parameter */ +#define PRINT_PROBABILITIES 0 /* set to 1 to print probabilities (for Ehrenfest urn configuration) */ +#define PRINT_NOISE 0 /* set to 1 to print noise intensity */ + +#define DRAW_FIELD_LINES 0 /* set to 1 to draw field lines */ +#define FIELD_LINE_WIDTH 1 /* width of field lines */ +#define N_FIELD_LINES 120 /* number of field lines */ +#define FIELD_LINE_FACTOR 120 /* factor controlling precision when computing origin of field lines */ +#define DRAW_BILLIARD 1 /* set to 1 to draw boundary */ +#define DRAW_BILLIARD_FRONT 1 /* set to 1 to draw boundary */ +#define FILL_BILLIARD_COMPLEMENT 1 /* set to 1 to fill complement of billiard (for certain shapes only) */ + +/* 3D representation */ + +#define REPRESENTATION_3D 1 /* choice of 3D representation */ + +#define REP_AXO_3D 0 /* linear projection (axonometry) */ +#define REP_PROJ_3D 1 /* projection on plane orthogonal to observer line of sight */ + +/* Color schemes, see list in global_pdes.c */ + +#define COLOR_PALETTE 13 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 14 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* black background */ + +#define COLOR_SCHEME 3 /* choice of color scheme */ + +#define COLOR_PHASE_SHIFT 0.0 /* phase shift of color scheme, in units of Pi */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define VSCALE_AMPLITUDE 2.0 /* additional scaling factor for color scheme P_3D_AMPLITUDE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define CURL_SCALE 0.000015 /* scaling factor for curl representation */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ +#define SLOPE_SCHROD_LUM 50.0 /* sensitivity of luminosity on module, for color scheme Z_ARGUMENT */ +#define MIN_SCHROD_LUM 0.2 /* minimal luminosity in color scheme Z_ARGUMENT*/ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 359.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -359.0 /* amplitude of variation of hue for color scheme C_HUE */ +#define E_SCALE 100.0 /* scaling factor for energy representation */ +#define LOG_SCALE 1.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 + +#define DRAW_COLOR_SCHEME 0 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 3.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 2.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +/* only for compatibility with wave_common.c */ +#define TWOSPEEDS 0 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OMEGA 0.005 /* frequency of periodic excitation */ +#define COURANT 0.08 /* Courant number */ +#define COURANTB 0.03 /* Courant number in medium B */ +#define INITIAL_AMP 0.5 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.1 /* wavelength of initial condition */ +#define VSCALE_ENERGY 200.0 /* additional scaling factor for color scheme P_3D_ENERGY */ +#define PHASE_FACTOR 20.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define OSCILLATION_SCHEDULE 0 /* oscillation schedule, see list in global_pdes.c */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.2 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ +#define NXMAZE 8 /* width of maze */ +#define NYMAZE 8 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 58 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ +/* end of constants added only for compatibility with wave_common.c */ + + +double u_3d[2] = {0.75, -0.45}; /* projections of basis vectors for REP_AXO_3D representation */ +double v_3d[2] = {-0.75, -0.45}; +double w_3d[2] = {0.0, 0.015}; +double light[3] = {0.816496581, -0.40824829, 0.40824829}; /* vector of "light" direction for P_3D_ANGLE color scheme */ +double observer[3] = {8.0, 8.0, 8.0}; /* location of observer for REP_PROJ_3D representation */ +int reset_view = 0; /* switch to reset 3D view parameters (for option ROTATE_VIEW) */ + +#define Z_SCALING_FACTOR 1.0 /* overall scaling factor of z axis for REP_PROJ_3D representation */ +#define XY_SCALING_FACTOR 1.8 /* overall scaling factor for on-screen (x,y) coordinates after projection */ +#define ZMAX_FACTOR 1.0 /* max value of z coordinate for REP_PROJ_3D representation */ +#define XSHIFT_3D -0.1 /* overall x shift for REP_PROJ_3D representation */ +#define YSHIFT_3D 0.0 /* overall y shift for REP_PROJ_3D representation */ +#define BORDER_PADDING 2 /* distance from boundary at which to plot points, to avoid boundary effects due to gradient */ + +/* For debugging purposes only */ +#define FLOOR 1 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ +#define TEST_GRADIENT 0 /* print norm squared of gradient */ + +``` + +### 16 October 22 - A rocket that can rotate ### + +**Program:** `lennardjones.c` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 0 /* set to 1 to produce movies for wave height and energy simultaneously */ + +#define TIME_LAPSE 1 /* set to 1 to add a time-lapse movie at the end */ + /* so far incompatible with double movie */ +#define TIME_LAPSE_FACTOR 3 /* factor of time-lapse movie */ +#define TIME_LAPSE_FIRST 1 /* set to 1 to show time-lapse version first */ + +/* General geometrical parameters */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -3.3 +#define XMAX 4.7 /* x interval */ +#define YMIN -2.25 +#define YMAX 2.25 /* y interval for 9/16 aspect ratio */ + +#define INITXMIN -0.7 +#define INITXMAX 0.7 /* x interval for initial condition */ +#define INITYMIN -1.7 +#define INITYMAX 2.5 /* y interval for initial condition */ + +#define BCXMIN -5.1 +#define BCXMAX 6.1 /* x interval for boundary condition */ +#define BCYMIN -6.5 +#define BCYMAX 15.5 /* y interval for boundary condition */ + +#define OBSXMIN -2.0 +#define OBSXMAX 2.0 /* x interval for motion of obstacle */ + +#define CIRCLE_PATTERN 8 /* pattern of circles, see list in global_ljones.c */ + +#define ADD_FIXED_OBSTACLES 0 /* set to 1 do add fixed circular obstacles */ +#define OBSTACLE_PATTERN 3 /* pattern of obstacles, see list in global_ljones.c */ + +#define ADD_FIXED_SEGMENTS 1 /* set to 1 to add fixed segments as obstacles */ +#define SEGMENT_PATTERN 101 /* pattern of repelling segments, see list in global_ljones.c */ +#define ROCKET_SHAPE 1 /* shape of rocket combustion chamber, see list in global_ljones.c */ +#define ROCKET_SHAPE_B 0 /* shape of second rocket */ +#define NOZZLE_SHAPE 1 /* shape of nozzle, see list in global_ljones.c */ +#define NOZZLE_SHAPE_B 4 /* shape of nozzle for second rocket, see list in global_ljones.c */ + +#define TWO_TYPES 0 /* set to 1 to have two types of particles */ +#define TPYE_PROPORTION 0.5 /* proportion of particles of first type */ +#define SYMMETRIZE_FORCE 1 /* set to 1 to symmetrize two-particle interaction, only needed if particles are not all the same */ +#define CENTER_PX 0 /* set to 1 to center horizontal momentum */ +#define CENTER_PY 0 /* set to 1 to center vertical momentum */ +#define CENTER_PANGLE 0 /* set to 1 to center angular momentum */ + +#define INTERACTION 1 /* particle interaction, see list in global_ljones.c */ +#define INTERACTION_B 1 /* particle interaction for second type of particle, see list in global_ljones.c */ +#define SPIN_INTER_FREQUENCY 5.0 /* angular frequency of spin-spin interaction */ +#define SPIN_INTER_FREQUENCY_B 2.0 /* angular frequency of spin-spin interaction for second particle type */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 100 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define PDISC_DISTANCE 2.5 /* minimal distance in Poisson disc process, controls density of particles */ +#define PDISC_CANDIDATES 100 /* number of candidates in construction of Poisson disc process */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.8 /* parameter controlling the dimensions of domain */ +#define MU 0.0075 /* parameter controlling radius of particles */ +#define MU_B 0.018 /* parameter controlling radius of particles of second type */ +#define NPOLY 25 /* number of sides of polygon */ +#define APOLY 0.666666666 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 4 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 90 /* number of grid point for grid of disks */ +#define NGRIDY 100 /* number of grid point for grid of disks */ +#define EHRENFEST_RADIUS 0.9 /* radius of container for Ehrenfest urn configuration */ +#define EHRENFEST_WIDTH 0.035 /* width of tube for Ehrenfest urn configuration */ +#define TWO_CIRCLES_RADIUS_RATIO 0.8 /* ratio of radii for S_TWO_CIRCLES_EXT segment configuration */ +#define DAM_WIDTH 0.05 /* width of dam for S_DAM segment configuration */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 1750 /* number of frames of movie */ +#define NVID 100 /* number of iterations between images displayed on screen */ +#define NSEG 250 /* number of segments of boundary */ +#define INITIAL_TIME 10 /* time after which to start saving frames */ +#define OBSTACLE_INITIAL_TIME 200 /* time after which to start moving obstacle */ +#define BOUNDARY_WIDTH 1 /* width of particle boundary */ +#define LINK_WIDTH 2 /* width of links between particles */ +#define CONTAINER_WIDTH 4 /* width of container boundary */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ + +/* Boundary conditions, see list in global_ljones.c */ + +#define BOUNDARY_COND 20 + +/* Plot type, see list in global_ljones.c */ + +#define PLOT 0 +#define PLOT_B 8 /* plot type for second movie */ + +#define DRAW_BONDS 0 /* set to 1 to draw bonds between neighbours */ +#define COLOR_BONDS 1 /* set to 1 to color bonds according to length */ +#define FILL_TRIANGLES 1 /* set to 1 to fill triangles between neighbours */ + +/* Color schemes */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_ljones.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_ljones.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 0.5 /* sensitivity of color on wave amplitude */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 220.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -50.0 /* amplitude of variation of hue for color scheme C_HUE */ + +/* particle properties */ + +#define ENERGY_HUE_MIN 330.0 /* color of original particle */ +#define ENERGY_HUE_MAX 50.0 /* color of saturated particle */ +#define PARTICLE_HUE_MIN 359.0 /* color of original particle */ +#define PARTICLE_HUE_MAX 0.0 /* color of saturated particle */ +#define PARTICLE_EMAX 2.0e2 /* energy of particle with hottest color */ +#define HUE_TYPE0 70.0 /* hue of particles of type 0 */ +#define HUE_TYPE1 280.0 /* hue of particles of type 1 */ +#define HUE_TYPE2 .0 /* hue of particles of type 2 */ +#define HUE_TYPE3 210.0 /* hue of particles of type 3 */ + +#define RANDOM_RADIUS 0 /* set to 1 for random circle radius */ +#define DT_PARTICLE 3.0e-6 /* time step for particle displacement */ +#define KREPEL 12.0 /* constant in repelling force between particles */ +#define EQUILIBRIUM_DIST 4.5 /* Lennard-Jones equilibrium distance */ +#define EQUILIBRIUM_DIST_B 3.5 /* Lennard-Jones equilibrium distance for second type of particle */ +#define REPEL_RADIUS 20.0 /* radius in which repelling force acts (in units of particle radius) */ +#define DAMPING 5.0 /* damping coefficient of particles */ +#define PARTICLE_MASS 1.0 /* mass of particle of radius MU */ +#define PARTICLE_MASS_B 1.0 /* mass of particle of radius MU */ +#define PARTICLE_INERTIA_MOMENT 0.2 /* moment of inertia of particle */ +#define PARTICLE_INERTIA_MOMENT_B 0.02 /* moment of inertia of second type of particle */ +#define V_INITIAL 0.0 /* initial velocity range */ +#define OMEGA_INITIAL 10.0 /* initial angular velocity range */ + +#define THERMOSTAT 1 /* set to 1 to switch on thermostat */ +#define VARY_THERMOSTAT 0 /* set to 1 for time-dependent thermostat schedule */ +#define SIGMA 5.0 /* noise intensity in thermostat */ +#define BETA 0.02 /* initial inverse temperature */ +#define MU_XI 0.01 /* friction constant in thermostat */ +#define KSPRING_BOUNDARY 1.0e7 /* confining harmonic potential outside simulation region */ +#define KSPRING_OBSTACLE 1.0e11 /* harmonic potential of obstacles */ +#define NBH_DIST_FACTOR 7.5 /* radius in which to count neighbours */ +#define GRAVITY 15.0 /* gravity acting on all particles */ +#define GRAVITY_X 0.0 /* horizontal gravity acting on all particles */ +#define INCREASE_GRAVITY 0 /* set to 1 to increase gravity during the simulation */ +#define GRAVITY_SCHEDULE 2 /* type of gravity schedule, see list in global_ljones.c */ +#define GRAVITY_FACTOR 100.0 /* factor by which to increase gravity */ +#define GRAVITY_INITIAL_TIME 200 /* time at start of simulation with constant gravity */ +#define GRAVITY_RESTORE_TIME 700 /* time at end of simulation with gravity restored to initial value */ + +#define ROTATION 0 /* set to 1 to include rotation of particles */ +#define COUPLE_ANGLE_TO_THERMOSTAT 0 /* set to 1 to couple angular degrees of freedom to thermostat */ +#define DIMENSION_FACTOR 1.0 /* scaling factor taking into account number of degrees of freedom */ +#define KTORQUE 100.0 /* force constant in angular dynamics */ +#define KTORQUE_B 10.0 /* force constant in angular dynamics */ +#define KTORQUE_DIFF 150.0 /* force constant in angular dynamics for different particles */ +#define DRAW_SPIN 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_SPIN_B 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_CROSS 1 /* set to 1 to draw cross on particles of second type */ +#define SPIN_RANGE 7.0 /* range of spin-spin interaction */ +#define SPIN_RANGE_B 5.0 /* range of spin-spin interaction for second type of particle */ +#define QUADRUPOLE_RATIO 0.6 /* anisotropy in quadrupole potential */ + +#define INCREASE_BETA 1 /* set to 1 to increase BETA during simulation */ +#define BETA_FACTOR 0.025 /* factor by which to change BETA during simulation */ +#define N_TOSCILLATIONS 1.5 /* number of temperature oscillations in BETA schedule */ +#define NO_OSCILLATION 1 /* set to 1 to have exponential BETA change only */ +#define MIDDLE_CONSTANT_PHASE 850 /* final phase in which temperature is constant */ +#define FINAL_DECREASE_PHASE 700 /* final phase in which temperature decreases */ +#define FINAL_CONSTANT_PHASE -1 /* final phase in which temperature is constant */ + +#define DECREASE_CONTAINER_SIZE 0 /* set to 1 to decrease size of container */ +#define SYMMETRIC_DECREASE 0 /* set tp 1 to decrease container symmetrically */ +#define COMPRESSION_RATIO 0.3 /* final size of container */ +#define RESTORE_CONTAINER_SIZE 1 /* set to 1 to restore container to initial size at end of simulation */ +#define RESTORE_TIME 700 /* time before end of sim at which to restore size */ + +#define MOVE_OBSTACLE 0 /* set to 1 to have a moving obstacle */ +#define CENTER_VIEW_ON_OBSTACLE 0 /* set to 1 to center display on moving obstacle */ +#define RESAMPLE_Y 0 /* set to 1 to resample y coordinate of moved particles (for shock waves) */ +#define NTRIALS 2000 /* number of trials when resampling */ +#define OBSTACLE_RADIUS 0.12 /* radius of obstacle for circle boundary conditions */ +#define FUNNEL_WIDTH 0.25 /* funnel width for funnel boundary conditions */ +#define OBSTACLE_XMIN 0.0 /* initial position of obstacle */ +#define OBSTACLE_XMAX 3.0 /* final position of obstacle */ +#define RECORD_PRESSURES 0 /* set to 1 to record pressures on obstacle */ +#define N_PRESSURES 100 /* number of intervals to record pressure */ +#define N_P_AVERAGE 100 /* size of pressure averaging window */ +#define N_T_AVERAGE 50 /* size of temperature averaging window */ +#define MAX_PRESSURE 3.0e10 /* pressure shown in "hottest" color */ +#define PARTIAL_THERMO_COUPLING 0 /* set to 1 to couple only particles to the right of obstacle to thermostat */ +#define PARTIAL_THERMO_REGION 1 /* region for partial thermostat coupling (see list in global_ljones.c) */ +#define PARTIAL_THERMO_SHIFT 0.2 /* distance from obstacle at the right of which particles are coupled to thermostat */ +#define PARTIAL_THERMO_WIDTH 0.5 /* vertical size of partial thermostat coupling */ +#define PARTIAL_THERMO_HEIGHT 0.2 /* vertical size of partial thermostat coupling */ + +#define INCREASE_KREPEL 0 /* set to 1 to increase KREPEL during simulation */ +#define KREPEL_FACTOR 1000.0 /* factor by which to change KREPEL during simulation */ + +#define PART_AT_BOTTOM 0 /* set to 1 to include "seed" particles at bottom */ +#define MASS_PART_BOTTOM 10000.0 /* mass of particles at bottom */ +#define NPART_BOTTOM 100 /* number of particles at the bottom */ + +#define ADD_PARTICLES 0 /* set to 1 to add particles */ +#define ADD_TIME 0 /* time at which to add first particle */ +#define ADD_PERIOD 10000 /* time interval between adding further particles */ +#define FINAL_NOADD_PERIOD 200 /* final period where no particles are added */ +#define SAFETY_FACTOR 2.0 /* no particles are added at distance less than MU*SAFETY_FACTOR of other particles */ + +#define TRACER_PARTICLE 0 /* set to 1 to have a tracer particle */ +#define N_TRACER_PARTICLES 3 /* number of tracer particles */ +#define TRAJECTORY_LENGTH 8000 /* length of recorded trajectory */ +#define TRACER_PARTICLE_MASS 4.0 /* relative mass of tracer particle */ +#define TRAJECTORY_WIDTH 3 /* width of tracer particle trajectory */ + +#define ROTATE_BOUNDARY 0 /* set to 1 to rotate the repelling segments */ +#define SMOOTH_ROTATION 1 /* set to 1 to update segments at each time step (rather than at each movie frame) */ +#define PERIOD_ROTATE_BOUNDARY 1000 /* period of rotating boundary */ +#define ROTATE_INITIAL_TIME 0 /* initial time without rotation */ +#define ROTATE_FINAL_TIME 100 /* final time without rotation */ +#define ROTATE_CHANGE_TIME 0.33 /* relative duration of acceleration/deceleration phases */ +#define OMEGAMAX 100.0 /* maximal rotation speed */ +#define PRINT_OMEGA 0 /* set to 1 to print angular speed */ +#define PRINT_PARTICLE_SPEEDS 0 /* set to 1 to print average speeds/momenta of particles */ +#define PRINT_SEGMENTS_SPEEDS 1 /* set to 1 to print velocity of moving segments */ + +#define MOVE_BOUNDARY 0 /* set to 1 to move repelling segments, due to force from particles */ +#define SEGMENTS_MASS 40.0 /* mass of collection of segments */ +#define DEACTIVATE_SEGMENT 1 /* set to 1 to deactivate last segment after a certain time */ +#define SEGMENT_DEACTIVATION_TIME 200 /* time at which to deactivate last segment */ +#define RELEASE_ROCKET_AT_DEACTIVATION 1 /* set to 1 to limit segments velocity before segment release */ +#define SEGMENTS_X0 0.0 /* initial position of segments */ +#define SEGMENTS_Y0 0.0 /* initial position of segments */ +#define SEGMENTS_VX0 0.0 /* initial velocity of segments */ +#define SEGMENTS_VY0 0.0 /* initial velocity of segments */ +#define DAMP_SEGS_AT_NEGATIVE_Y 0 /* set to 1 to dampen segments when y coordinate is negative */ + +#define MOVE_SEGMENT_GROUPS 1 /* set to 1 to group segments into moving units */ +#define SEGMENT_GROUP_MASS 900.0 /* mass of segment group */ +#define SEGMENT_GROUP_I 25.0 /* moment of inertia of segment group */ +#define SEGMENT_GROUP_DAMPING 0.0 /* damping of segment groups */ +#define GROUP_REPULSION 0 /* set to 1 for groups of segments to repel each other */ +#define KSPRING_GROUPS 1.0e8 /* harmonic potential between segment groups */ +#define GROUP_WIDTH 0.05 /* interaction width of groups */ +#define GROUP_G_REPEL 0 /* set to 1 to add repulsion between centers of mass of groups */ +#define GROUP_G_REPEL_RADIUS 0.12 /* radius within which centers of mass of groups repel each other */ + +#define POSITION_DEPENDENT_TYPE 0 /* set to 1 to make particle type depend on initial position */ +#define POSITION_Y_DEPENDENCE 0 /* set to 1 for the separation between particles to be horizontal */ +#define PRINT_ENTROPY 0 /* set to 1 to compute entropy */ + +#define REACTION_DIFFUSION 0 /* set to 1 to simulate a chemical reaction (particles may change type) */ +#define RD_TYPES 3 /* number of types in reaction-diffusion equation */ +#define REACTION_PROB 0.0045 /* probability controlling reaction term */ + +#define PRINT_PARTICLE_NUMBER 0 /* set to 1 to print total number of particles */ +#define PRINT_LEFT 1 /* set to 1 to print certain parameters at the top left instead of right */ +#define PLOT_SPEEDS 1 /* set to 1 to add a plot of obstacle speeds (e.g. for rockets) */ +#define VMAX_PLOT_SPEEDS 0.5 /* vertical scale of plot of obstacle speeds */ + +#define EHRENFEST_COPY 0 /* set to 1 to add equal number of larger particles (for Ehrenfest model) */ + +#define LID_MASS 1000.0 /* mass of lid for BC_RECTANGLE_LID b.c. */ +#define LID_WIDTH 0.1 /* width of lid for BC_RECTANGLE_LID b.c. */ +#define WALL_MASS 2000.0 /* mass of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_FRICTION 0.0 /* friction on wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_WIDTH 0.1 /* width of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_VMAX 100.0 /* max speed of wall */ +#define WALL_TIME 0 /* time during which to keep wall */ + +#define NXMAZE 10 /* width of maze */ +#define NYMAZE 10 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 200 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +#define FLOOR_FORCE 1 /* set to 1 to limit force on particle to FMAX */ +#define FMAX 1.0e12 /* maximal force */ +#define FLOOR_OMEGA 0 /* set to 1 to limit particle momentum to PMAX */ +#define PMAX 1000.0 /* maximal force */ + +#define HASHX 160 /* size of hashgrid in x direction */ +#define HASHY 320 /* size of hashgrid in y direction */ +#define HASHMAX 100 /* maximal number of particles per hashgrid cell */ +#define HASHGRID_PADDING 0.1 /* padding of hashgrid outside simulation window */ + +#define DRAW_COLOR_SCHEME 0 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 8.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 12.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +``` + +### 15 October 22 - And the winner is: The fastest particles solving a maze ### + +**Program:** `particle_billiard.c` + +**Initial condition in function `animation()`:** `init_drop_config(-1.3, 0.2, -0.25*PI, 0.25*PI, configs);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define SCALING_FACTOR 1.0 /* scaling factor of drawing, needed for flower billiards, otherwise set to 1.0 */ + +/* Choice of the billiard table, see global_particles.c */ + +#define B_DOMAIN 30 /* choice of domain shape */ + +#define CIRCLE_PATTERN 1 /* pattern of circles */ +#define POLYLINE_PATTERN 10 /* pattern of polyline */ + +#define ABSORBING_CIRCLES 1 /* set to 1 for circular scatterers to be absorbing */ + +#define NMAXCIRCLES 100000 /* total number of circles (must be at least NCX*NCY for square grid) */ +#define NMAXPOLY 100000 /* total number of sides of polygonal line */ +#define NCX 30 /* number of circles in x direction */ +#define NCY 20 /* number of circles in y direction */ +#define NPOISSON 500 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define NGOLDENSPIRAL 2000 /* max number of points for C_GOLDEN_SPIRAL arrandement */ +#define SDEPTH 1 /* Sierpinski gastket depth */ + +#define LAMBDA 1.5 /* parameter controlling shape of domain */ +#define MU 0.5 /* second parameter controlling shape of billiard */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NPOLY 6 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define PENROSE_RATIO 2.5 /* parameter controlling the shape of small ellipses in Penrose room */ + +#define DRAW_BILLIARD 1 /* set to 1 to draw billiard */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw additional construction lines for billiard */ +#define PERIODIC_BC 0 /* set to 1 to enforce periodic boundary conditions when drawing particles */ + +#define RESAMPLE 0 /* set to 1 if particles should be added when dispersion too large */ +#define DEBUG 0 /* draw trajectories, for debugging purposes */ + +/* Simulation parameters */ + +#define NPART 1000 /* number of particles */ +#define NPARTMAX 100000 /* maximal number of particles after resampling */ +#define LMAX 0.01 /* minimal segment length triggering resampling */ +#define DMIN 0.02 /* minimal distance to boundary for triggering resampling */ +#define CYCLE 1 /* set to 1 for closed curve (start in all directions) */ +#define SHOWTRAILS 1 /* set to 1 to keep trails of the particles */ +#define SHOWZOOM 0 /* set to 1 to show zoom on specific area */ +#define PRINT_PARTICLE_NUMBER 0 /* set to 1 to print number of particles */ +#define PRINT_LEFT_RIGHT_PARTICLE_NUMBER 1 /* set to 1 to print number of particles on left and right side */ +#define PRINT_COLLISION_NUMBER 0 /* set to 1 to print number of collisions */ +#define TEST_ACTIVE 1 /* set to 1 to test whether particle is in billiard */ + +#define TEST_INITIAL_COND 1 /* set to 1 to allow only initial conditions that pass a test */ + +#define NSTEPS 6000 /* number of frames of movie */ +#define TIME 1500 /* time between movie frames, for fluidity of real-time simulation */ +#define DPHI 0.00002 /* integration step */ +#define NVID 25 /* number of iterations between images displayed on screen */ +#define END_FRAMES 25 /* number of still frames at the end of the movie */ + +/* Decreasing TIME accelerates the animation and the movie */ +/* For constant speed of movie, TIME*DPHI should be kept constant */ +/* However, increasing DPHI too much deterioriates quality of simulation */ +/* NVID tells how often a picture is drawn in the animation, increase it for faster anim */ +/* For a good quality movie, take for instance TIME = 400, DPHI = 0.00005, NVID = 100 */ + +/* Colors and other graphical parameters */ + +#define COLOR_PALETTE 11 /* Color palette, see list in global_pdes.c */ + +#define NCOLORS 16 /* number of colors */ +#define COLORSHIFT 0 /* hue of initial color */ +#define RAINBOW_COLOR 1 /* set to 1 to use different colors for all particles */ +#define FLOWER_COLOR 0 /* set to 1 to adapt initial colors to flower billiard (tracks vs core) */ +#define NSEG 100 /* number of segments of boundary */ +#define LENGTH 0.04 /* length of velocity vectors */ +#define BILLIARD_WIDTH 3 /* width of billiard */ +#define PARTICLE_WIDTH 3 /* width of particles */ +#define FRONT_WIDTH 3 /* width of wave front */ + +#define BLACK 1 /* set to 1 for black background */ +#define COLOR_OUTSIDE 0 /* set to 1 for colored outside */ +#define OUTER_COLOR 270.0 /* color outside billiard */ +#define PAINT_INT 0 /* set to 1 to paint interior in other color (for polygon/Reuleaux) */ +#define PAINT_EXT 1 /* set to 1 to paint exterior */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ + +#define NXMAZE 8 /* width of maze */ +#define NYMAZE 8 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 58 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +``` + +### 14 October 22 - solving a maze with waves: Average energy ### + +**Program:** `wave_billiard.c` + +**Initial condition in function `animation()`:** + +``` + init_circular_wave(-1.5, 0.0, phi, psi, xy_in); + + add_circular_wave(sign, -1.5, 0.0, phi, psi, xy_in); + sign = -sign; +``` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 3840 /* number of grid points on x axis */ +#define NY 2000 /* number of grid points on y axis */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +#define HIGHRES 1 /* set to 1 if resolution of grid is double that of displayed image */ + +#define JULIA_SCALE 1.0 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 53 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 1 /* pattern of circles or polygons, see list in global_pdes.c */ + +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 1 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.0 /* parameter controlling the dimensions of domain */ +#define MU 0.3 /* parameter controlling the dimensions of domain */ +#define NPOLY 6 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 6 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 12 /* number of grid point for grid of disks */ +#define NGRIDY 15 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -2.9 +#define ISO_XSHIFT_RIGHT 1.4 +#define ISO_YSHIFT_LEFT -0.15 +#define ISO_YSHIFT_RIGHT -0.15 +#define ISO_SCALE 0.5 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard below */ + +/* Physical parameters of wave equation */ + +#define TWOSPEEDS 0 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OSCILLATE_LEFT 0 /* set to 1 to add oscilating boundary condition on the left */ +#define OSCILLATE_TOPBOT 0 /* set to 1 to enforce a planar wave on top and bottom boundary */ +#define OSCILLATION_SCHEDULE 1 /* oscillation schedule, see list in global_pdes.c */ + +#define OMEGA 0.0005 /* frequency of periodic excitation */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.25 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COURANT 0.12 /* Courant number */ +#define COURANTB 0.06 /* Courant number in medium B */ +#define GAMMA 0.0 /* damping factor in wave equation */ +#define GAMMAB 0.0 /* damping factor in wave equation */ +#define GAMMA_SIDES 1.0e-4 /* damping factor on boundary */ +#define GAMMA_TOPBOT 1.0e-7 /* damping factor on boundary */ +#define KAPPA 0.0 /* "elasticity" term enforcing oscillations */ +#define KAPPA_SIDES 5.0e-4 /* "elasticity" term on absorbing boundary */ +#define KAPPA_TOPBOT 0.0 /* "elasticity" term on absorbing boundary */ +/* The Courant number is given by c*DT/DX, where DT is the time step and DX the lattice spacing */ +/* The physical damping coefficient is given by GAMMA/(DT)^2 */ +/* Increasing COURANT speeds up the simulation, but decreases accuracy */ +/* For similar wave forms, COURANT^2*GAMMA should be kept constant */ + +#define ADD_OSCILLATING_SOURCE 1 /* set to 1 to add an oscillating wave source */ +#define OSCILLATING_SOURCE_PERIOD 25 /* period of oscillating source */ + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 2 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 2500 /* number of frames of movie */ +#define NVID 20 /* number of iterations between images displayed on screen */ +#define NSEG 1000 /* number of segments of boundary */ +#define INITIAL_TIME 0 /* time after which to start saving frames */ +#define BOUNDARY_WIDTH 2 /* width of billiard boundary */ +#define PRINT_SPEED 0 /* print speed of moving source */ + +#define PAUSE 200 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Parameters of initial condition */ + +#define INITIAL_AMP 0.75 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.01 /* wavelength of initial condition */ + +/* Plot type, see list in global_pdes.c */ + +#define PLOT 3 +#define PLOT_B 5 /* plot type for second movie */ + +/* Color schemes */ + +#define COLOR_PALETTE 13 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 14 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_pdes.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define PHASE_FACTOR 1.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define E_SCALE 125.0 /* scaling factor for energy representation */ +#define LOG_SCALE 1.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 /* shift of colors on log scale */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 180.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -180.0 /* amplitude of variation of hue for color scheme C_HUE */ + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 2.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 1.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +#define SAVE_TIME_SERIES 0 /* set to 1 to save wave time series at a point */ + +#define NXMAZE 7 /* width of maze */ +#define NYMAZE 7 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 24 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +/* For debugging purposes only */ +#define FLOOR 0 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ + +``` + +### 13 October 22 - 3D rendering of two interacting vortices in the 2D incompressible Euler equation ### + +**Program:** `rde.c` + +**Initial condition in function `animation()`:** + +``` + init_vortex_state(0.5, 0.0, 0.2, phi, xy_in); + add_vortex_state(-0.5, 0.0, 0.2, phi, xy_in); +``` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 920 /* number of grid points on x axis */ +#define NY 450 /* number of grid points on y axis */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +/* Choice of simulated equation */ + +#define RDE_EQUATION 6 /* choice of reaction term, see list in global_3d.c */ +#define NFIELDS 2 /* number of fields in reaction-diffusion equation */ +#define NLAPLACIANS 1 /* number of fields for which to compute Laplacian */ + +#define ADD_POTENTIAL 0 /* set to 1 to add a potential (for Schrodinger equation) */ +#define ADD_MAGNETIC_FIELD 0 /* set to 1 to add a magnetic field (for Schrodinger equation) - then set POTENTIAL 1 */ +#define POTENTIAL 101 /* type of potential or vector potential, see list in global_3d.c */ + +#define ANTISYMMETRIZE_WAVE_FCT 0 /* set tot 1 to make wave function antisymmetric */ + +#define JULIA_SCALE 0.5 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 999 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 99 /* pattern of circles, see list in global_pdes.c */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 1.0 /* parameter controlling the dimensions of domain */ +#define MU 1.0 /* parameter controlling the dimensions of domain */ +#define NPOLY 5 /* number of sides of polygon */ +#define APOLY 2.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 7 /* depth of computation of Menger gasket */ +#define MRATIO 5 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 15 /* number of grid point for grid of disks */ +#define NGRIDY 20 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -1.65 +#define ISO_XSHIFT_RIGHT 0.4 +#define ISO_YSHIFT_LEFT -0.05 +#define ISO_YSHIFT_RIGHT -0.05 +#define ISO_SCALE 0.85 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard in sub_wave.c */ + +/* Physical patameters of wave equation */ + +#define DT 0.0000012 + +#define VISCOSITY 2.0 + +#define RPSA 0.75 /* parameter in Rock-Paper-Scissors-type interaction */ +#define RPSLZB 0.75 /* second parameter in Rock-Paper-Scissors-Lizard-Spock type interaction */ + +#define EPSILON 0.8 /* time scale separation */ +#define DELTA 0.1 /* time scale separation */ +#define FHNA 1.0 /* parameter in FHN equation */ +#define FHNC -0.01 /* parameter in FHN equation */ +#define K_HARMONIC 1.0 /* spring constant of harmonic potential */ +#define K_COULOMB 0.5 /* constant in Coulomb potential */ +#define BZQ 0.0008 /* parameter in BZ equation */ +#define BZF 1.2 /* parameter in BZ equation */ +#define B_FIELD 10.0 /* magnetic field */ +#define AB_RADIUS 0.2 /* radius of region with magnetic field for Aharonov-Bohm effect */ +#define K_EULER 50.0 /* constant in stream function integration of Euler equation */ + +#define SMOOTHEN_VORTICITY 1 /* set to 1 to smoothen vorticity field in Euler equation */ +#define SMOOTHEN_PERIOD 12 /* period between smoothenings */ +#define SMOOTH_FACTOR 0.01 /* factor by which to smoothen */ + +#define T_OUT 2.0 /* outside temperature */ +#define T_IN 0.0 /* inside temperature */ +#define SPEED 0.0 /* speed of drift to the right */ + +#define ADD_NOISE 0 /* set to 1 to add noise, set to 2 to add noise in right half */ +#define NOISE_INTENSITY 0.005 /* noise intensity */ +#define CHANGE_NOISE 1 /* set to 1 to increase noise intensity */ +#define NOISE_FACTOR 40.0 /* factor by which to increase noise intensity */ +#define NOISE_INITIAL_TIME 100 /* initial time during which noise remains constant */ + +#define CHANGE_VISCOSITY 0 /* set to 1 to change the viscosity in the course of the simulation */ +#define ADJUST_INTSTEP 0 /* set to 1 to decrease integration step when viscosity increases */ +#define VISCOSITY_INITIAL_TIME 10 /* initial time during which viscosity remains constant */ +#define VISCOSITY_FACTOR 100.0 /* factor by which to change viscosity */ +#define VISCOSITY_MAX 2.0 /* max value of viscosity beyond which NVID is increased and integration step is decrase, + for numerical stability */ + +#define CHANGE_RPSLZB 0 /* set to 1 to change second parameter in Rock-Paper-Scissors-Lizard-Spock equation */ +#define RPSLZB_CHANGE 0.75 /* factor by which to rpslzb parameter */ +#define RPSLZB_INITIAL_TIME 0 /* initial time during which rpslzb remains constant */ +#define RPSLZB_FINAL_TIME 500 /* final time during which rpslzb remains constant */ + + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 1 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 2500 /* number of frames of movie */ +#define NVID 250 /* number of iterations between images displayed on screen */ +#define ACCELERATION_FACTOR 1.0 /* factor by which to increase NVID in course of simulation */ +#define DT_ACCELERATION_FACTOR 1.0 /* factor by which to increase time step in course of simulation */ +#define MAX_DT 0.024 /* maximal value of integration step */ +#define NSEG 100 /* number of segments of boundary */ +#define BOUNDARY_WIDTH 5 /* width of billiard boundary */ + +#define PAUSE 100 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 2 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define INITIAL_TIME 0 /* initial still time */ +#define MID_FRAMES 50 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 50 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Visualisation */ + +#define PLOT_3D 1 /* controls whether plot is 2D or 3D */ + +#define ROTATE_VIEW 0 /* set to 1 to rotate position of observer */ +#define ROTATE_ANGLE 360.0 /* total angle of rotation during simulation */ + +/* Plot type - color scheme */ + +#define CPLOT 50 +#define CPLOT_B 51 + +/* Plot type - height of 3D plot */ + +#define ZPLOT 50 /* z coordinate in 3D plot */ +#define ZPLOT_B 51 /* z coordinate in second 3D plot */ + +#define AMPLITUDE_HIGH_RES 1 /* set to 1 to increase resolution of P_3D_AMPLITUDE plot */ +#define SHADE_3D 1 /* set to 1 to change luminosity according to normal vector */ +#define NON_DIRICHLET_BC 0 /* set to 1 to draw only facets in domain, if field is not zero on boundary */ +#define WRAP_ANGLE 1 /* experimental: wrap angle to [0, 2Pi) for interpolation in angle schemes */ +#define FADE_IN_OBSTACLE 0 /* set to 1 to fade color inside obstacles */ +#define DRAW_OUTSIDE_GRAY 0 /* experimental - draw outside of billiard in gray */ +#define ADD_POTENTIAL_TO_Z 1 /* set to 1 to add the external potential to z-coordinate of plot */ +#define ADD_POT_CONSTANT 0.5 /* constant in front of added potential */ + +#define PLOT_SCALE_ENERGY 0.05 /* vertical scaling in energy plot */ + +#define PRINT_TIME 0 /* set to 1 to print running time */ +#define PRINT_VISCOSITY 0 /* set to 1 to print viscosity */ +#define PRINT_RPSLZB 0 /* set to 1 to print rpslzb parameter */ +#define PRINT_PROBABILITIES 0 /* set to 1 to print probabilities (for Ehrenfest urn configuration) */ +#define PRINT_NOISE 0 /* set to 1 to print noise intensity */ + +#define DRAW_FIELD_LINES 0 /* set to 1 to draw field lines */ +#define FIELD_LINE_WIDTH 1 /* width of field lines */ +#define N_FIELD_LINES 120 /* number of field lines */ +#define FIELD_LINE_FACTOR 120 /* factor controlling precision when computing origin of field lines */ +#define DRAW_BILLIARD 1 /* set to 1 to draw boundary */ +#define DRAW_BILLIARD_FRONT 1 /* set to 1 to draw boundary */ +#define FILL_BILLIARD_COMPLEMENT 1 /* set to 1 to fill complement of billiard (for certain shapes only) */ + +/* 3D representation */ + +#define REPRESENTATION_3D 1 /* choice of 3D representation */ + +#define REP_AXO_3D 0 /* linear projection (axonometry) */ +#define REP_PROJ_3D 1 /* projection on plane orthogonal to observer line of sight */ + +/* Color schemes, see list in global_pdes.c */ + +#define COLOR_PALETTE 11 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 14 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* black background */ + +#define COLOR_SCHEME 3 /* choice of color scheme */ + +#define COLOR_PHASE_SHIFT 0.0 /* phase shift of color scheme, in units of Pi */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define VSCALE_AMPLITUDE 2.0 /* additional scaling factor for color scheme P_3D_AMPLITUDE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define CURL_SCALE 0.000015 /* scaling factor for curl representation */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ +#define SLOPE_SCHROD_LUM 50.0 /* sensitivity of luminosity on module, for color scheme Z_ARGUMENT */ +#define MIN_SCHROD_LUM 0.2 /* minimal luminosity in color scheme Z_ARGUMENT*/ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 359.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -359.0 /* amplitude of variation of hue for color scheme C_HUE */ +#define E_SCALE 100.0 /* scaling factor for energy representation */ +#define LOG_SCALE 1.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 3.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 2.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +/* only for compatibility with wave_common.c */ +#define TWOSPEEDS 0 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OMEGA 0.005 /* frequency of periodic excitation */ +#define COURANT 0.08 /* Courant number */ +#define COURANTB 0.03 /* Courant number in medium B */ +#define INITIAL_AMP 0.5 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.1 /* wavelength of initial condition */ +#define VSCALE_ENERGY 200.0 /* additional scaling factor for color scheme P_3D_ENERGY */ +#define PHASE_FACTOR 20.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define OSCILLATION_SCHEDULE 0 /* oscillation schedule, see list in global_pdes.c */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.2 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ +#define NXMAZE 8 /* width of maze */ +#define NYMAZE 8 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 58 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ +/* end of constants added only for compatibility with wave_common.c */ + + +double u_3d[2] = {0.75, -0.45}; /* projections of basis vectors for REP_AXO_3D representation */ +double v_3d[2] = {-0.75, -0.45}; +double w_3d[2] = {0.0, 0.015}; +double light[3] = {0.816496581, -0.40824829, 0.40824829}; /* vector of "light" direction for P_3D_ANGLE color scheme */ +double observer[3] = {8.0, 8.0, 8.0}; /* location of observer for REP_PROJ_3D representation */ +int reset_view = 0; /* switch to reset 3D view parameters (for option ROTATE_VIEW) */ + +#define Z_SCALING_FACTOR 1.0 /* overall scaling factor of z axis for REP_PROJ_3D representation */ +#define XY_SCALING_FACTOR 1.8 /* overall scaling factor for on-screen (x,y) coordinates after projection */ +#define ZMAX_FACTOR 1.0 /* max value of z coordinate for REP_PROJ_3D representation */ +#define XSHIFT_3D -0.1 /* overall x shift for REP_PROJ_3D representation */ +#define YSHIFT_3D 0.0 /* overall y shift for REP_PROJ_3D representation */ +#define BORDER_PADDING 2 /* distance from boundary at which to plot points, to avoid boundary effects due to gradient */ + +/* For debugging purposes only */ +#define FLOOR 1 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ +#define TEST_GRADIENT 0 /* print norm squared of gradient */ + +``` + +### 12 October 22 - Phase space representation of a Penrose unilluminable room ### + +**Program:** `billiard_phase_space.c` + +**In function `animation()`:** `lyap_exponents[i] = draw_phase_portrait(20, 20, 100, 20, 0.2);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define XPHASEMAX 0.0 /* max x coordinate of phase portrait */ + +#define PIXELIZE 1 /* set to 1 to pixelize phase portrait (beta) */ +#define NGRID 200 /* size of grid to draw orbits with positive Lyapunov exponent */ + +#define SCALING_FACTOR 1.0 /* scaling factor of drawing, needed for flower billiards, otherwise set to 1.0 */ + +/* Choice of the billiard table, see global_particles.c */ + +#define B_DOMAIN 16 /* choice of domain shape */ + +#define CIRCLE_PATTERN 6 /* pattern of circles */ +#define POLYLINE_PATTERN 4 /* pattern of polyline */ + +#define ABSORBING_CIRCLES 1 /* set to 1 for circular scatterers to be absorbing */ + +#define NMAXCIRCLES 50000 /* total number of circles (must be at least NCX*NCY for square grid) */ +#define NMAXPOLY 50000 /* total number of sides of polygonal line */ +#define NCX 9 /* number of circles in x direction */ +#define NCY 20 /* number of circles in y direction */ +#define NPOISSON 500 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define NGOLDENSPIRAL 2000 /* max number of points for C_GOLDEN_SPIRAL arrandement */ +#define SDEPTH 2 /* Sierpinski gastket depth */ + +#define LAMBDA 1.5 /* parameter controlling shape of domain */ +#define MU 0.3 /* second parameter controlling shape of billiard */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NPOLY 4 /* number of sides of polygon */ +#define APOLY -1.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define DRAW_BILLIARD 1 /* set to 1 to draw billiard */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw additional construction lines for billiard */ +#define PERIODIC_BC 0 /* set to 1 to enforce periodic boundary conditions when drawing particles */ +#define PENROSE_RATIO 9.0 /* parameter controlling the shape of small ellipses in Penrose room */ + +#define RESAMPLE 0 /* set to 1 if particles should be added when dispersion too large */ +#define DEBUG 0 /* draw trajectories, for debugging purposes */ + +/* Simulation parameters */ + +#define NPART 1 /* number of particles */ +#define NPARTMAX 100000 /* maximal number of particles after resampling */ +#define TRAJ_LENGTH 10000 /* length of trajectory */ +#define LMAX 0.01 /* minimal segment length triggering resampling */ +#define DMIN 0.02 /* minimal distance to boundary for triggering resampling */ +#define CYCLE 1 /* set to 1 for closed curve (start in all directions) */ +#define SHOWTRAILS 0 /* set to 1 to keep trails of the particles */ +#define SHOWZOOM 0 /* set to 1 to show zoom on specific area */ +#define TEST_ACTIVE 1 /* set to 1 to test whether particle is in billiard */ +#define PRINT_TRAJECTORY_LENGTH 0 /* set to 1 to print length of trajectory 0 */ +#define PRINT_TRAJECTORY_PERIOD 0 /* set to 1 to print period of trajectory 0 */ +#define DRAW_LENGTHS_PLOT 0 /* set to 1 to plot trajectory lengths */ +#define LENGTHS_LOG_SCALE 1 /* set to 1 to use log scale for plot of lengths */ +#define MAX_ANGLE 90.0 /* range of angles of trajectory */ + +#define NSTEPS 2800 /* number of frames of movie */ +#define TIME 2500 /* time between movie frames, for fluidity of real-time simulation */ +#define DPHI 0.00001 /* integration step */ +#define NVID 150 /* number of iterations between images displayed on screen */ +#define SYMMETRIC_PARAMETER 1 /* set to 1 if parameters depend symmetrically on time */ + +/* Decreasing TIME accelerates the animation and the movie */ +/* For constant speed of movie, TIME*DPHI should be kept constant */ +/* However, increasing DPHI too much deterioriates quality of simulation */ +/* NVID tells how often a picture is drawn in the animation, increase it for faster anim */ +/* For a good quality movie, take for instance TIME = 400, DPHI = 0.00005, NVID = 100 */ + +/* Colors and other graphical parameters */ + +#define COLOR_PALETTE 14 /* Color palette, see list in global_pdes.c */ + +#define NCOLORS 64 /* number of colors */ +#define CFACTOR 3 /* color step */ +#define COLORSHIFT 0 /* hue of initial color */ +#define LYAP_PLOT_COLOR 200.0 /* color hue of Lyapunov exponent plot */ +#define RAINBOW_COLOR 0 /* set to 1 to use different colors for all particles */ +#define FLOWER_COLOR 0 /* set to 1 to adapt initial colors to flower billiard (tracks vs core) */ +#define NSEG 100 /* number of segments of boundary */ +#define LENGTH 0.03 /* length of velocity vectors */ +#define BILLIARD_WIDTH 2 /* width of billiard */ +#define PARTICLE_WIDTH 2 /* width of particles */ +#define FRONT_WIDTH 3 /* width of wave front */ + +#define BLACK 1 /* set to 1 for black background */ +#define COLOR_OUTSIDE 0 /* set to 1 for colored outside */ +#define OUTER_COLOR 270.0 /* color outside billiard */ +#define PAINT_INT 0 /* set to 1 to paint interior in other color (for polygon/Reuleaux) */ +#define PAINT_EXT 1 /* set to 1 to paint exterior */ + +#define PRINT_LAMBDA 0 /* set to 1 to print value of lambda */ +#define PRINT_MU 0 /* set to 1 to print value of mu */ +#define PRINT_PENROSE_RATIO 1 /* set to 1 to print value of the Penrose billiard ratio */ +#define PRINT_LYAPUNOV 1 /* set to 1 to print mean Lyapunov exponent */ +#define PLOT_LYAPUNOV 1 /* set to 1 to add plot of Lyapunov exponents */ +#define LOGSCALEX_LYAP 0 /* set to 1 to use log scale on parameter axis of Lyapunov exponents */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define END_FRAMES 100 /* number of frames at end of movie */ + +``` + +### 11 October 22 - solving a maze with waves ### + +**Program:** `wave_billiard.c` + +**Initial condition in function `animation()`:** + +``` + init_circular_wave(-1.5, 0.0, phi, psi, xy_in); + + add_circular_wave(sign, -1.5, 0.0, phi, psi, xy_in); + sign = -sign; +``` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 3840 /* number of grid points on x axis */ +#define NY 2000 /* number of grid points on y axis */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +#define HIGHRES 1 /* set to 1 if resolution of grid is double that of displayed image */ + +#define JULIA_SCALE 1.0 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 53 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 1 /* pattern of circles or polygons, see list in global_pdes.c */ + +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 1 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.0 /* parameter controlling the dimensions of domain */ +#define MU 0.3 /* parameter controlling the dimensions of domain */ +#define NPOLY 6 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 6 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 12 /* number of grid point for grid of disks */ +#define NGRIDY 15 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -2.9 +#define ISO_XSHIFT_RIGHT 1.4 +#define ISO_YSHIFT_LEFT -0.15 +#define ISO_YSHIFT_RIGHT -0.15 +#define ISO_SCALE 0.5 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard below */ + +/* Physical parameters of wave equation */ + +#define TWOSPEEDS 0 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OSCILLATE_LEFT 0 /* set to 1 to add oscilating boundary condition on the left */ +#define OSCILLATE_TOPBOT 0 /* set to 1 to enforce a planar wave on top and bottom boundary */ +#define OSCILLATION_SCHEDULE 1 /* oscillation schedule, see list in global_pdes.c */ + +#define OMEGA 0.0005 /* frequency of periodic excitation */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.25 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COURANT 0.12 /* Courant number */ +#define COURANTB 0.06 /* Courant number in medium B */ +#define GAMMA 0.0 /* damping factor in wave equation */ +#define GAMMAB 0.0 /* damping factor in wave equation */ +#define GAMMA_SIDES 1.0e-4 /* damping factor on boundary */ +#define GAMMA_TOPBOT 1.0e-7 /* damping factor on boundary */ +#define KAPPA 0.0 /* "elasticity" term enforcing oscillations */ +#define KAPPA_SIDES 5.0e-4 /* "elasticity" term on absorbing boundary */ +#define KAPPA_TOPBOT 0.0 /* "elasticity" term on absorbing boundary */ +/* The Courant number is given by c*DT/DX, where DT is the time step and DX the lattice spacing */ +/* The physical damping coefficient is given by GAMMA/(DT)^2 */ +/* Increasing COURANT speeds up the simulation, but decreases accuracy */ +/* For similar wave forms, COURANT^2*GAMMA should be kept constant */ + +#define ADD_OSCILLATING_SOURCE 1 /* set to 1 to add an oscillating wave source */ +#define OSCILLATING_SOURCE_PERIOD 25 /* period of oscillating source */ + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 2 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 3000 /* number of frames of movie */ +#define NVID 10 /* number of iterations between images displayed on screen */ +#define NSEG 1000 /* number of segments of boundary */ +#define INITIAL_TIME 0 /* time after which to start saving frames */ +#define BOUNDARY_WIDTH 2 /* width of billiard boundary */ +#define PRINT_SPEED 0 /* print speed of moving source */ + +#define PAUSE 200 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Parameters of initial condition */ + +#define INITIAL_AMP 0.75 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.01 /* wavelength of initial condition */ + +/* Plot type, see list in global_pdes.c */ + +#define PLOT 0 + +#define PLOT_B 4 /* plot type for second movie */ + +/* Color schemes */ + +#define COLOR_PALETTE 11 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 13 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_pdes.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define PHASE_FACTOR 1.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define E_SCALE 125.0 /* scaling factor for energy representation */ +#define LOG_SCALE 1.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 /* shift of colors on log scale */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 180.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -180.0 /* amplitude of variation of hue for color scheme C_HUE */ + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 2.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 1.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +#define SAVE_TIME_SERIES 0 /* set to 1 to save wave time series at a point */ + +#define NXMAZE 7 /* width of maze */ +#define NYMAZE 7 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 24 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +/* For debugging purposes only */ +#define FLOOR 0 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ + +``` + +### 10 October 22 - Shining a rotating laser beam into a maze with mirrored walls ### + +**Program:** `particle_trajectory.c` + +**Initial condition in function `animation()`:** + +``` + time = (double)i/(double)(NSTEPS-1); + x = -1.65; + y = 0.22; + alpha = angle_schedule(time); +``` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define SCALING_FACTOR 1.0 /* scaling factor of drawing, needed for flower billiards, otherwise set to 1.0 */ + +/* Choice of the billiard table, see global_particles.c */ + +#define B_DOMAIN 30 /* choice of domain shape */ + +#define CIRCLE_PATTERN 6 /* pattern of circles */ +#define POLYLINE_PATTERN 10 /* pattern of polyline */ + +#define ABSORBING_CIRCLES 1 /* set to 1 for circular scatterers to be absorbing */ + +#define NMAXCIRCLES 50000 /* total number of circles (must be at least NCX*NCY for square grid) */ +#define NMAXPOLY 50000 /* total number of sides of polygonal line */ +#define NCX 9 /* number of circles in x direction */ +#define NCY 20 /* number of circles in y direction */ +#define NPOISSON 500 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define NGOLDENSPIRAL 2000 /* max number of points for C_GOLDEN_SPIRAL arrandement */ +#define SDEPTH 2 /* Sierpinski gastket depth */ + +#define LAMBDA -1.1 /* parameter controlling shape of domain */ +#define MU 0.1 /* second parameter controlling shape of billiard */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NPOLY 3 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define DRAW_BILLIARD 1 /* set to 1 to draw billiard */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw additional construction lines for billiard */ +#define PERIODIC_BC 0 /* set to 1 to enforce periodic boundary conditions when drawing particles */ +#define PENROSE_RATIO 2.5 /* parameter controlling the shape of small ellipses in Penrose room */ + +#define RESAMPLE 0 /* set to 1 if particles should be added when dispersion too large */ +#define DEBUG 0 /* draw trajectories, for debugging purposes */ + +/* Simulation parameters */ + +#define NPART 1 /* number of particles */ +#define NPARTMAX 100000 /* maximal number of particles after resampling */ +#define TRAJ_LENGTH 10000 /* length of trajectory */ +#define LMAX 0.01 /* minimal segment length triggering resampling */ +#define DMIN 0.02 /* minimal distance to boundary for triggering resampling */ +#define CYCLE 1 /* set to 1 for closed curve (start in all directions) */ +#define SHOWTRAILS 0 /* set to 1 to keep trails of the particles */ +#define SHOWZOOM 0 /* set to 1 to show zoom on specific area */ +#define TEST_ACTIVE 1 /* set to 1 to test whether particle is in billiard */ +#define PRINT_TRAJECTORY_LENGTH 1 /* set to 1 to print length of trajectory 0 */ +#define PRINT_TRAJECTORY_ANGLE 1 /* set to 1 to print angle of trajectory 0 */ +#define PRINT_TRAJECTORY_PERIOD 0 /* set to 1 to print period of trajectory 0 */ +#define DRAW_LENGTHS_PLOT 1 /* set to 1 to plot trajectory lengths */ +#define LENGTHS_LOG_SCALE 1 /* set to 1 to use log scale for plot of lengths */ +#define MAX_ANGLE 45.0 /* range of angles of trajectory */ + +#define NSTEPS 3600 /* number of frames of movie */ +#define TIME 2500 /* time between movie frames, for fluidity of real-time simulation */ +#define DPHI 0.00001 /* integration step */ +#define NVID 150 /* number of iterations between images displayed on screen */ + +/* Decreasing TIME accelerates the animation and the movie */ +/* For constant speed of movie, TIME*DPHI should be kept constant */ +/* However, increasing DPHI too much deterioriates quality of simulation */ +/* NVID tells how often a picture is drawn in the animation, increase it for faster anim */ +/* For a good quality movie, take for instance TIME = 400, DPHI = 0.00005, NVID = 100 */ + +/* Colors and other graphical parameters */ + +#define COLOR_PALETTE 14 /* Color palette, see list in global_pdes.c */ + +#define NCOLORS 64 /* number of colors */ +#define COLORSHIFT 0 /* hue of initial color */ +#define RAINBOW_COLOR 0 /* set to 1 to use different colors for all particles */ +#define FLOWER_COLOR 0 /* set to 1 to adapt initial colors to flower billiard (tracks vs core) */ +#define NSEG 100 /* number of segments of boundary */ +#define LENGTH 0.03 /* length of velocity vectors */ +#define BILLIARD_WIDTH 2 /* width of billiard */ +#define PARTICLE_WIDTH 2 /* width of particles */ +#define FRONT_WIDTH 3 /* width of wave front */ + +#define BLACK 1 /* set to 1 for black background */ +#define COLOR_OUTSIDE 0 /* set to 1 for colored outside */ +#define OUTER_COLOR 270.0 /* color outside billiard */ +#define PAINT_INT 0 /* set to 1 to paint interior in other color (for polygon/Reuleaux) */ +#define PAINT_EXT 1 /* set to 1 to paint exterior */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define END_FRAMES 100 /* number of frames at end of movie */ + +#define NXMAZE 8 /* width of maze */ +#define NYMAZE 8 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 58 /* seed of random number generator */ +#define MAZE_XSHIFT -0.5 /* horizontal shift of maze */ + +``` + +### 9 October 22 - Video #600: Incompressible Euler equation with two vortices ### + +**Program:** `rde.c` + +**Initial condition in function `animation()`:** +``` + init_vortex_state(0.4, 0.0, 0.2, phi, xy_in); + add_vortex_state(-0.4, 0.0, 0.2, phi, xy_in);` +``` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 960 /* number of grid points on x axis */ +#define NY 500 /* number of grid points on y axis */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +/* Choice of simulated equation */ + +#define RDE_EQUATION 6 /* choice of reaction term, see list in global_3d.c */ +#define NFIELDS 2 /* number of fields in reaction-diffusion equation */ +#define NLAPLACIANS 1 /* number of fields for which to compute Laplacian */ + +#define ADD_POTENTIAL 0 /* set to 1 to add a potential (for Schrodinger equation) */ +#define ADD_MAGNETIC_FIELD 0 /* set to 1 to add a magnetic field (for Schrodinger equation) - then set POTENTIAL 1 */ +#define POTENTIAL 101 /* type of potential or vector potential, see list in global_3d.c */ + +#define ANTISYMMETRIZE_WAVE_FCT 0 /* set tot 1 to make wave function antisymmetric */ + +#define JULIA_SCALE 0.5 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 999 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 99 /* pattern of circles, see list in global_pdes.c */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 1.0 /* parameter controlling the dimensions of domain */ +#define MU 1.0 /* parameter controlling the dimensions of domain */ +#define NPOLY 5 /* number of sides of polygon */ +#define APOLY 2.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 7 /* depth of computation of Menger gasket */ +#define MRATIO 5 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 15 /* number of grid point for grid of disks */ +#define NGRIDY 20 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -1.65 +#define ISO_XSHIFT_RIGHT 0.4 +#define ISO_YSHIFT_LEFT -0.05 +#define ISO_YSHIFT_RIGHT -0.05 +#define ISO_SCALE 0.85 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard in sub_wave.c */ + +/* Physical patameters of wave equation */ + +#define DT 0.000001 + +#define VISCOSITY 2.0 + +#define RPSA 0.75 /* parameter in Rock-Paper-Scissors-type interaction */ +#define RPSLZB 0.75 /* second parameter in Rock-Paper-Scissors-Lizard-Spock type interaction */ + +#define EPSILON 0.8 /* time scale separation */ +#define DELTA 0.1 /* time scale separation */ +#define FHNA 1.0 /* parameter in FHN equation */ +#define FHNC -0.01 /* parameter in FHN equation */ +#define K_HARMONIC 1.0 /* spring constant of harmonic potential */ +#define K_COULOMB 0.5 /* constant in Coulomb potential */ +#define BZQ 0.0008 /* parameter in BZ equation */ +#define BZF 1.2 /* parameter in BZ equation */ +#define B_FIELD 10.0 /* magnetic field */ +#define AB_RADIUS 0.2 /* radius of region with magnetic field for Aharonov-Bohm effect */ +#define K_EULER 50.0 /* constant in stream function integration of Euler equation */ + +#define T_OUT 2.0 /* outside temperature */ +#define T_IN 0.0 /* inside temperature */ +#define SPEED 0.0 /* speed of drift to the right */ + +#define ADD_NOISE 0 /* set to 1 to add noise, set to 2 to add noise in right half */ +#define NOISE_INTENSITY 0.005 /* noise intensity */ +#define CHANGE_NOISE 1 /* set to 1 to increase noise intensity */ +#define NOISE_FACTOR 40.0 /* factor by which to increase noise intensity */ +#define NOISE_INITIAL_TIME 100 /* initial time during which noise remains constant */ + +#define CHANGE_VISCOSITY 0 /* set to 1 to change the viscosity in the course of the simulation */ +#define ADJUST_INTSTEP 0 /* set to 1 to decrease integration step when viscosity increases */ +#define VISCOSITY_INITIAL_TIME 10 /* initial time during which viscosity remains constant */ +#define VISCOSITY_FACTOR 100.0 /* factor by which to change viscosity */ +#define VISCOSITY_MAX 2.0 /* max value of viscosity beyond which NVID is increased and integration step is decrase, + for numerical stability */ + +#define CHANGE_RPSLZB 0 /* set to 1 to change second parameter in Rock-Paper-Scissors-Lizard-Spock equation */ +#define RPSLZB_CHANGE 0.75 /* factor by which to rpslzb parameter */ +#define RPSLZB_INITIAL_TIME 0 /* initial time during which rpslzb remains constant */ +#define RPSLZB_FINAL_TIME 500 /* final time during which rpslzb remains constant */ + + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 1 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 3000 /* number of frames of movie */ +#define NVID 200 /* number of iterations between images displayed on screen */ +#define ACCELERATION_FACTOR 1.0 /* factor by which to increase NVID in course of simulation */ +#define DT_ACCELERATION_FACTOR 1.0 /* factor by which to increase time step in course of simulation */ +#define MAX_DT 0.024 /* maximal value of integration step */ +#define NSEG 100 /* number of segments of boundary */ +#define BOUNDARY_WIDTH 5 /* width of billiard boundary */ + +#define PAUSE 100 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 2 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define INITIAL_TIME 0 /* initial still time */ +#define MID_FRAMES 50 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 50 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Visualisation */ + +#define PLOT_3D 0 /* controls whether plot is 2D or 3D */ + +#define ROTATE_VIEW 0 /* set to 1 to rotate position of observer */ +#define ROTATE_ANGLE 360.0 /* total angle of rotation during simulation */ + +/* Plot type - color scheme */ + +#define CPLOT 50 +#define CPLOT_B 51 + +/* Plot type - height of 3D plot */ + +#define ZPLOT 50 /* z coordinate in 3D plot */ +#define ZPLOT_B 51 /* z coordinate in second 3D plot */ + +#define AMPLITUDE_HIGH_RES 1 /* set to 1 to increase resolution of P_3D_AMPLITUDE plot */ +#define SHADE_3D 1 /* set to 1 to change luminosity according to normal vector */ +#define NON_DIRICHLET_BC 0 /* set to 1 to draw only facets in domain, if field is not zero on boundary */ +#define WRAP_ANGLE 1 /* experimental: wrap angle to [0, 2Pi) for interpolation in angle schemes */ +#define FADE_IN_OBSTACLE 0 /* set to 1 to fade color inside obstacles */ +#define DRAW_OUTSIDE_GRAY 0 /* experimental - draw outside of billiard in gray */ +#define ADD_POTENTIAL_TO_Z 1 /* set to 1 to add the external potential to z-coordinate of plot */ +#define ADD_POT_CONSTANT 0.5 /* constant in front of added potential */ + +#define PLOT_SCALE_ENERGY 0.05 /* vertical scaling in energy plot */ + +#define PRINT_TIME 0 /* set to 1 to print running time */ +#define PRINT_VISCOSITY 0 /* set to 1 to print viscosity */ +#define PRINT_RPSLZB 0 /* set to 1 to print rpslzb parameter */ +#define PRINT_PROBABILITIES 0 /* set to 1 to print probabilities (for Ehrenfest urn configuration) */ +#define PRINT_NOISE 0 /* set to 1 to print noise intensity */ + +#define DRAW_FIELD_LINES 0 /* set to 1 to draw field lines */ +#define FIELD_LINE_WIDTH 1 /* width of field lines */ +#define N_FIELD_LINES 120 /* number of field lines */ +#define FIELD_LINE_FACTOR 120 /* factor controlling precision when computing origin of field lines */ +#define DRAW_BILLIARD 1 /* set to 1 to draw boundary */ +#define DRAW_BILLIARD_FRONT 1 /* set to 1 to draw boundary */ +#define FILL_BILLIARD_COMPLEMENT 1 /* set to 1 to fill complement of billiard (for certain shapes only) */ + +/* 3D representation */ + +#define REPRESENTATION_3D 1 /* choice of 3D representation */ + +#define REP_AXO_3D 0 /* linear projection (axonometry) */ +#define REP_PROJ_3D 1 /* projection on plane orthogonal to observer line of sight */ + +/* Color schemes, see list in global_pdes.c */ + +#define COLOR_PALETTE 11 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 14 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* black background */ + +#define COLOR_SCHEME 3 /* choice of color scheme */ + +#define COLOR_PHASE_SHIFT 0.0 /* phase shift of color scheme, in units of Pi */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 1.0 /* sensitivity of color on wave amplitude */ +#define VSCALE_AMPLITUDE 1.5 /* additional scaling factor for color scheme P_3D_AMPLITUDE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define CURL_SCALE 0.000015 /* scaling factor for curl representation */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ +#define SLOPE_SCHROD_LUM 50.0 /* sensitivity of luminosity on module, for color scheme Z_ARGUMENT */ +#define MIN_SCHROD_LUM 0.2 /* minimal luminosity in color scheme Z_ARGUMENT*/ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 359.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -359.0 /* amplitude of variation of hue for color scheme C_HUE */ +#define E_SCALE 100.0 /* scaling factor for energy representation */ +#define LOG_SCALE 2.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT -1.0 + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 2.5 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 2.5 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +/* only for compatibility with wave_common.c */ +#define TWOSPEEDS 0 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OMEGA 0.005 /* frequency of periodic excitation */ +#define COURANT 0.08 /* Courant number */ +#define COURANTB 0.03 /* Courant number in medium B */ +#define INITIAL_AMP 0.5 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.1 /* wavelength of initial condition */ +#define VSCALE_ENERGY 200.0 /* additional scaling factor for color scheme P_3D_ENERGY */ +#define PHASE_FACTOR 20.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define OSCILLATION_SCHEDULE 0 /* oscillation schedule, see list in global_pdes.c */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.2 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ +#define NXMAZE 8 /* width of maze */ +#define NYMAZE 8 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 58 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ +/* end of constants added only for compatibility with wave_common.c */ + + +double u_3d[2] = {0.75, -0.45}; /* projections of basis vectors for REP_AXO_3D representation */ +double v_3d[2] = {-0.75, -0.45}; +double w_3d[2] = {0.0, 0.015}; +double light[3] = {0.816496581, -0.40824829, 0.40824829}; /* vector of "light" direction for P_3D_ANGLE color scheme */ +double observer[3] = {8.0, 8.0, 12.0}; /* location of observer for REP_PROJ_3D representation */ +int reset_view = 0; /* switch to reset 3D view parameters (for option ROTATE_VIEW) */ + +#define Z_SCALING_FACTOR 1.25 /* overall scaling factor of z axis for REP_PROJ_3D representation */ +#define XY_SCALING_FACTOR 1.8 /* overall scaling factor for on-screen (x,y) coordinates after projection */ +#define ZMAX_FACTOR 1.0 /* max value of z coordinate for REP_PROJ_3D representation */ +#define XSHIFT_3D -0.1 /* overall x shift for REP_PROJ_3D representation */ +#define YSHIFT_3D 0.0 /* overall y shift for REP_PROJ_3D representation */ + + +/* For debugging purposes only */ +#define FLOOR 1 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ +#define TEST_GRADIENT 0 /* print norm squared of gradient */ + +``` + +### 8 October 22 - An example of a simulation gone wrong: Dam break with interacting bricks and no thermostat ### + +**Program:** `lennardjones.c` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 0 /* set to 1 to produce movies for wave height and energy simultaneously */ + +#define TIME_LAPSE 1 /* set to 1 to add a time-lapse movie at the end */ + /* so far incompatible with double movie */ +#define TIME_LAPSE_FACTOR 3 /* factor of time-lapse movie */ +#define TIME_LAPSE_FIRST 1 /* set to 1 to show time-lapse version first */ + +/* General geometrical parameters */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define INITXMIN -2.0 +#define INITXMAX -0.04 /* x interval for initial condition */ +#define INITYMIN -1.125 +#define INITYMAX 0.65 /* y interval for initial condition */ + +#define BCXMIN -2.05 +#define BCXMAX 2.0 /* x interval for boundary condition */ +#define BCYMIN -1.125 +#define BCYMAX 1.25 /* y interval for boundary condition */ + +#define OBSXMIN -2.0 +#define OBSXMAX 2.0 /* x interval for motion of obstacle */ + +#define CIRCLE_PATTERN 1 /* pattern of circles, see list in global_ljones.c */ + +#define ADD_FIXED_OBSTACLES 0 /* set to 1 do add fixed circular obstacles */ +#define OBSTACLE_PATTERN 3 /* pattern of obstacles, see list in global_ljones.c */ + +#define ADD_FIXED_SEGMENTS 1 /* set to 1 to add fixed segments as obstacles */ +#define SEGMENT_PATTERN 17 /* pattern of repelling segments, see list in global_ljones.c */ +#define ROCKET_SHAPE 0 /* shape of rocket combustion chamber, see list in global_ljones.c */ +#define ROCKET_SHAPE_B 0 /* shape of second rocket */ +#define NOZZLE_SHAPE 1 /* shape of nozzle, see list in global_ljones.c */ +#define NOZZLE_SHAPE_B 4 /* shape of nozzle for second rocket, see list in global_ljones.c */ + +#define TWO_TYPES 0 /* set to 1 to have two types of particles */ +#define TPYE_PROPORTION 0.5 /* proportion of particles of first type */ +#define SYMMETRIZE_FORCE 1 /* set to 1 to symmetrize two-particle interaction, only needed if particles are not all the same */ +#define CENTER_PX 0 /* set to 1 to center horizontal momentum */ +#define CENTER_PY 0 /* set to 1 to center vertical momentum */ +#define CENTER_PANGLE 0 /* set to 1 to center angular momentum */ + +#define INTERACTION 1 /* particle interaction, see list in global_ljones.c */ +#define INTERACTION_B 1 /* particle interaction for second type of particle, see list in global_ljones.c */ +#define SPIN_INTER_FREQUENCY 5.0 /* angular frequency of spin-spin interaction */ +#define SPIN_INTER_FREQUENCY_B 2.0 /* angular frequency of spin-spin interaction for second particle type */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 100 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define PDISC_DISTANCE 2.5 /* minimal distance in Poisson disc process, controls density of particles */ +#define PDISC_CANDIDATES 100 /* number of candidates in construction of Poisson disc process */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.8 /* parameter controlling the dimensions of domain */ +#define MU 0.0075 /* parameter controlling radius of particles */ +#define MU_B 0.018 /* parameter controlling radius of particles of second type */ +#define NPOLY 25 /* number of sides of polygon */ +#define APOLY 0.666666666 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 4 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 90 /* number of grid point for grid of disks */ +#define NGRIDY 100 /* number of grid point for grid of disks */ +#define EHRENFEST_RADIUS 0.9 /* radius of container for Ehrenfest urn configuration */ +#define EHRENFEST_WIDTH 0.035 /* width of tube for Ehrenfest urn configuration */ +#define TWO_CIRCLES_RADIUS_RATIO 0.8 /* ratio of radii for S_TWO_CIRCLES_EXT segment configuration */ +#define DAM_WIDTH 0.05 /* width of dam for S_DAM segment configuration */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 2400 /* number of frames of movie */ +#define NVID 60 /* number of iterations between images displayed on screen */ +#define NSEG 250 /* number of segments of boundary */ +#define INITIAL_TIME 10 /* time after which to start saving frames */ +#define OBSTACLE_INITIAL_TIME 250 /* time after which to start moving obstacle */ +#define BOUNDARY_WIDTH 1 /* width of particle boundary */ +#define LINK_WIDTH 2 /* width of links between particles */ +#define CONTAINER_WIDTH 4 /* width of container boundary */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ + +/* Boundary conditions, see list in global_ljones.c */ + +#define BOUNDARY_COND 0 + +/* Plot type, see list in global_ljones.c */ + +#define PLOT 11 +#define PLOT_B 11 /* plot type for second movie */ + +#define DRAW_BONDS 0 /* set to 1 to draw bonds between neighbours */ +#define COLOR_BONDS 1 /* set to 1 to color bonds according to length */ +#define FILL_TRIANGLES 1 /* set to 1 to fill triangles between neighbours */ + +/* Color schemes */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_ljones.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_ljones.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 0.5 /* sensitivity of color on wave amplitude */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 220.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -50.0 /* amplitude of variation of hue for color scheme C_HUE */ + +/* particle properties */ + +#define ENERGY_HUE_MIN 330.0 /* color of original particle */ +#define ENERGY_HUE_MAX 50.0 /* color of saturated particle */ +#define PARTICLE_HUE_MIN 359.0 /* color of original particle */ +#define PARTICLE_HUE_MAX 0.0 /* color of saturated particle */ +#define PARTICLE_EMAX 2.0e2 /* energy of particle with hottest color */ +#define HUE_TYPE0 70.0 /* hue of particles of type 0 */ +#define HUE_TYPE1 280.0 /* hue of particles of type 1 */ +#define HUE_TYPE2 .0 /* hue of particles of type 2 */ +#define HUE_TYPE3 210.0 /* hue of particles of type 3 */ + +#define RANDOM_RADIUS 0 /* set to 1 for random circle radius */ +#define DT_PARTICLE 3.0e-6 /* time step for particle displacement */ +#define KREPEL 12.0 /* constant in repelling force between particles */ +#define EQUILIBRIUM_DIST 3.5 /* Lennard-Jones equilibrium distance */ +#define EQUILIBRIUM_DIST_B 3.5 /* Lennard-Jones equilibrium distance for second type of particle */ +#define REPEL_RADIUS 20.0 /* radius in which repelling force acts (in units of particle radius) */ +#define DAMPING 20.0 /* damping coefficient of particles */ +#define PARTICLE_MASS 1.0 /* mass of particle of radius MU */ +#define PARTICLE_MASS_B 1.0 /* mass of particle of radius MU */ +#define PARTICLE_INERTIA_MOMENT 0.2 /* moment of inertia of particle */ +#define PARTICLE_INERTIA_MOMENT_B 0.02 /* moment of inertia of second type of particle */ +#define V_INITIAL 0.0 /* initial velocity range */ +#define OMEGA_INITIAL 10.0 /* initial angular velocity range */ + +#define THERMOSTAT 0 /* set to 1 to switch on thermostat */ +#define VARY_THERMOSTAT 0 /* set to 1 for time-dependent thermostat schedule */ +#define SIGMA 5.0 /* noise intensity in thermostat */ +#define BETA 0.005 /* initial inverse temperature */ +#define MU_XI 0.01 /* friction constant in thermostat */ +#define KSPRING_BOUNDARY 1.0e11 /* confining harmonic potential outside simulation region */ +#define KSPRING_OBSTACLE 1.0e11 /* harmonic potential of obstacles */ +#define NBH_DIST_FACTOR 7.5 /* radius in which to count neighbours */ +#define GRAVITY 2000.0 /* gravity acting on all particles */ +#define GRAVITY_X 0.0 /* horizontal gravity acting on all particles */ +#define INCREASE_GRAVITY 0 /* set to 1 to increase gravity during the simulation */ +#define GRAVITY_SCHEDULE 2 /* type of gravity schedule, see list in global_ljones.c */ +#define GRAVITY_FACTOR 100.0 /* factor by which to increase gravity */ +#define GRAVITY_INITIAL_TIME 200 /* time at start of simulation with constant gravity */ +#define GRAVITY_RESTORE_TIME 700 /* time at end of simulation with gravity restored to initial value */ + +#define ROTATION 0 /* set to 1 to include rotation of particles */ +#define COUPLE_ANGLE_TO_THERMOSTAT 0 /* set to 1 to couple angular degrees of freedom to thermostat */ +#define DIMENSION_FACTOR 1.0 /* scaling factor taking into account number of degrees of freedom */ +#define KTORQUE 100.0 /* force constant in angular dynamics */ +#define KTORQUE_B 10.0 /* force constant in angular dynamics */ +#define KTORQUE_DIFF 150.0 /* force constant in angular dynamics for different particles */ +#define DRAW_SPIN 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_SPIN_B 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_CROSS 1 /* set to 1 to draw cross on particles of second type */ +#define SPIN_RANGE 7.0 /* range of spin-spin interaction */ +#define SPIN_RANGE_B 5.0 /* range of spin-spin interaction for second type of particle */ +#define QUADRUPOLE_RATIO 0.6 /* anisotropy in quadrupole potential */ + +#define INCREASE_BETA 0 /* set to 1 to increase BETA during simulation */ +#define BETA_FACTOR 0.1 /* factor by which to change BETA during simulation */ +#define N_TOSCILLATIONS 1.5 /* number of temperature oscillations in BETA schedule */ +#define NO_OSCILLATION 1 /* set to 1 to have exponential BETA change only */ +#define MIDDLE_CONSTANT_PHASE 3000 /* final phase in which temperature is constant */ +#define FINAL_DECREASE_PHASE -1 /* final phase in which temperature decreases */ +#define FINAL_CONSTANT_PHASE -1 /* final phase in which temperature is constant */ + +#define DECREASE_CONTAINER_SIZE 0 /* set to 1 to decrease size of container */ +#define SYMMETRIC_DECREASE 0 /* set tp 1 to decrease container symmetrically */ +#define COMPRESSION_RATIO 0.3 /* final size of container */ +#define RESTORE_CONTAINER_SIZE 1 /* set to 1 to restore container to initial size at end of simulation */ +#define RESTORE_TIME 700 /* time before end of sim at which to restore size */ + +#define MOVE_OBSTACLE 0 /* set to 1 to have a moving obstacle */ +#define CENTER_VIEW_ON_OBSTACLE 0 /* set to 1 to center display on moving obstacle */ +#define RESAMPLE_Y 0 /* set to 1 to resample y coordinate of moved particles (for shock waves) */ +#define NTRIALS 2000 /* number of trials when resampling */ +#define OBSTACLE_RADIUS 0.12 /* radius of obstacle for circle boundary conditions */ +#define FUNNEL_WIDTH 0.25 /* funnel width for funnel boundary conditions */ +#define OBSTACLE_XMIN 0.0 /* initial position of obstacle */ +#define OBSTACLE_XMAX 3.0 /* final position of obstacle */ +#define RECORD_PRESSURES 0 /* set to 1 to record pressures on obstacle */ +#define N_PRESSURES 100 /* number of intervals to record pressure */ +#define N_P_AVERAGE 100 /* size of pressure averaging window */ +#define N_T_AVERAGE 50 /* size of temperature averaging window */ +#define MAX_PRESSURE 3.0e10 /* pressure shown in "hottest" color */ +#define PARTIAL_THERMO_COUPLING 0 /* set to 1 to couple only particles to the right of obstacle to thermostat */ +#define PARTIAL_THERMO_REGION 1 /* region for partial thermostat coupling (see list in global_ljones.c) */ +#define PARTIAL_THERMO_SHIFT 0.2 /* distance from obstacle at the right of which particles are coupled to thermostat */ +#define PARTIAL_THERMO_WIDTH 0.5 /* vertical size of partial thermostat coupling */ +#define PARTIAL_THERMO_HEIGHT 0.2 /* vertical size of partial thermostat coupling */ + +#define INCREASE_KREPEL 0 /* set to 1 to increase KREPEL during simulation */ +#define KREPEL_FACTOR 1000.0 /* factor by which to change KREPEL during simulation */ + +#define PART_AT_BOTTOM 0 /* set to 1 to include "seed" particles at bottom */ +#define MASS_PART_BOTTOM 10000.0 /* mass of particles at bottom */ +#define NPART_BOTTOM 100 /* number of particles at the bottom */ + +#define ADD_PARTICLES 0 /* set to 1 to add particles */ +#define ADD_TIME 0 /* time at which to add first particle */ +#define ADD_PERIOD 10000 /* time interval between adding further particles */ +#define FINAL_NOADD_PERIOD 200 /* final period where no particles are added */ +#define SAFETY_FACTOR 2.0 /* no particles are added at distance less than MU*SAFETY_FACTOR of other particles */ + +#define TRACER_PARTICLE 0 /* set to 1 to have a tracer particle */ +#define N_TRACER_PARTICLES 3 /* number of tracer particles */ +#define TRAJECTORY_LENGTH 8000 /* length of recorded trajectory */ +#define TRACER_PARTICLE_MASS 4.0 /* relative mass of tracer particle */ +#define TRAJECTORY_WIDTH 3 /* width of tracer particle trajectory */ + +#define ROTATE_BOUNDARY 0 /* set to 1 to rotate the repelling segments */ +#define SMOOTH_ROTATION 1 /* set to 1 to update segments at each time step (rather than at each movie frame) */ +#define PERIOD_ROTATE_BOUNDARY 1000 /* period of rotating boundary */ +#define ROTATE_INITIAL_TIME 0 /* initial time without rotation */ +#define ROTATE_FINAL_TIME 100 /* final time without rotation */ +#define ROTATE_CHANGE_TIME 0.33 /* relative duration of acceleration/deceleration phases */ +#define OMEGAMAX 100.0 /* maximal rotation speed */ +#define PRINT_OMEGA 0 /* set to 1 to print angular speed */ +#define PRINT_PARTICLE_SPEEDS 0 /* set to 1 to print average speeds/momenta of particles */ +#define PRINT_SEGMENTS_SPEEDS 0 /* set to 1 to print velocity of moving segments */ + +#define MOVE_BOUNDARY 0 /* set to 1 to move repelling segments, due to force from particles */ +#define SEGMENTS_MASS 40.0 /* mass of collection of segments */ +#define DEACTIVATE_SEGMENT 1 /* set to 1 to deactivate last segment after a certain time */ +#define SEGMENT_DEACTIVATION_TIME 200 /* time at which to deactivate last segment */ +#define RELEASE_ROCKET_AT_DEACTIVATION 1 /* set to 1 to limit segments velocity before segment release */ +#define SEGMENTS_X0 0.0 /* initial position of segments */ +#define SEGMENTS_Y0 0.0 /* initial position of segments */ +#define SEGMENTS_VX0 0.0 /* initial velocity of segments */ +#define SEGMENTS_VY0 0.0 /* initial velocity of segments */ +#define DAMP_SEGS_AT_NEGATIVE_Y 0 /* set to 1 to dampen segments when y coordinate is negative */ + +#define MOVE_SEGMENT_GROUPS 1 /* set to 1 to group segments into moving units */ +#define SEGMENT_GROUP_MASS 75.0 /* mass of segment group */ +#define SEGMENT_GROUP_I 15.0 /* moment of inertia of segment group */ +#define SEGMENT_GROUP_DAMPING 25.0 /* damping of segment groups */ +#define GROUP_REPULSION 1 /* set to 1 for groups of segments to repel each other */ +#define KSPRING_GROUPS 5.0e8 /* harmonic potential between segment groups */ +#define GROUP_WIDTH 0.05 /* interaction width of groups */ +#define GROUP_G_REPEL 1 /* set to 1 to add repulsion between centers of mass of groups */ +#define GROUP_G_REPEL_RADIUS 0.15 /* radius within which centers of mass of groups repel each other */ + +#define POSITION_DEPENDENT_TYPE 0 /* set to 1 to make particle type depend on initial position */ +#define POSITION_Y_DEPENDENCE 0 /* set to 1 for the separation between particles to be horizontal */ +#define PRINT_ENTROPY 0 /* set to 1 to compute entropy */ + +#define REACTION_DIFFUSION 0 /* set to 1 to simulate a chemical reaction (particles may change type) */ +#define RD_TYPES 3 /* number of types in reaction-diffusion equation */ +#define REACTION_PROB 0.0045 /* probability controlling reaction term */ + +#define PRINT_PARTICLE_NUMBER 0 /* set to 1 to print total number of particles */ +#define PRINT_LEFT 1 /* set to 1 to print certain parameters at the top left instead of right */ +#define PLOT_SPEEDS 0 /* set to 1 to add a plot of obstacle speeds (e.g. for rockets) */ +#define VMAX_PLOT_SPEEDS 5.0 /* vertical scale of plot of obstacle speeds */ + +#define EHRENFEST_COPY 0 /* set to 1 to add equal number of larger particles (for Ehrenfest model) */ + +#define LID_MASS 1000.0 /* mass of lid for BC_RECTANGLE_LID b.c. */ +#define LID_WIDTH 0.1 /* width of lid for BC_RECTANGLE_LID b.c. */ +#define WALL_MASS 2000.0 /* mass of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_FRICTION 0.0 /* friction on wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_WIDTH 0.1 /* width of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_VMAX 100.0 /* max speed of wall */ +#define WALL_TIME 0 /* time during which to keep wall */ + +#define FLOOR_FORCE 1 /* set to 1 to limit force on particle to FMAX */ +#define FMAX 1.0e12 /* maximal force */ +#define FLOOR_OMEGA 0 /* set to 1 to limit particle momentum to PMAX */ +#define PMAX 1000.0 /* maximal force */ + +#define HASHX 160 /* size of hashgrid in x direction */ +#define HASHY 80 /* size of hashgrid in y direction */ +#define HASHMAX 100 /* maximal number of particles per hashgrid cell */ +#define HASHGRID_PADDING 0.1 /* padding of hashgrid outside simulation window */ + +#define DRAW_COLOR_SCHEME 0 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 8.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 12.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +``` + +### 7 October 22 - Total internal reflection (short version) ### + +**Program:** `wave_billiard.c` + +**Initial condition in function `animation()`:** + +``` + init_circular_wave(-0.6, -0.3, phi, psi, xy_in); + + add_circular_wave(sign, -0.6, -0.3, phi, psi, xy_in); + sign = -sign; +``` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 0 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1000 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 2000 /* number of grid points on x axis */ +#define NY 2000 /* number of grid points on y axis */ + +#define XMIN -1.0 +#define XMAX 1.0 /* x interval */ +#define YMIN -1.0 +#define YMAX 1.0 /* y interval for 9/16 aspect ratio */ + +#define HIGHRES 1 /* set to 1 if resolution of grid is double that of displayed image */ + +#define JULIA_SCALE 1.0 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 6 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 1 /* pattern of circles or polygons, see list in global_pdes.c */ + +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 1 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.0 /* parameter controlling the dimensions of domain */ +#define MU 0.3 /* parameter controlling the dimensions of domain */ +#define NPOLY 6 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 6 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 12 /* number of grid point for grid of disks */ +#define NGRIDY 15 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -2.9 +#define ISO_XSHIFT_RIGHT 1.4 +#define ISO_YSHIFT_LEFT -0.15 +#define ISO_YSHIFT_RIGHT -0.15 +#define ISO_SCALE 0.5 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard below */ + +/* Physical parameters of wave equation */ + +#define TWOSPEEDS 1 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OSCILLATE_LEFT 0 /* set to 1 to add oscilating boundary condition on the left */ +#define OSCILLATE_TOPBOT 0 /* set to 1 to enforce a planar wave on top and bottom boundary */ +#define OSCILLATION_SCHEDULE 3 /* oscillation schedule, see list in global_pdes.c */ + +#define OMEGA 0.0005 /* frequency of periodic excitation */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.25 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COURANT 0.12 /* Courant number */ +#define COURANTB 0.06 /* Courant number in medium B */ +#define GAMMA 0.0 /* damping factor in wave equation */ +#define GAMMAB 0.0 /* damping factor in wave equation */ +#define GAMMA_SIDES 1.0e-4 /* damping factor on boundary */ +#define GAMMA_TOPBOT 1.0e-7 /* damping factor on boundary */ +#define KAPPA 0.0 /* "elasticity" term enforcing oscillations */ +#define KAPPA_SIDES 5.0e-4 /* "elasticity" term on absorbing boundary */ +#define KAPPA_TOPBOT 0.0 /* "elasticity" term on absorbing boundary */ +/* The Courant number is given by c*DT/DX, where DT is the time step and DX the lattice spacing */ +/* The physical damping coefficient is given by GAMMA/(DT)^2 */ +/* Increasing COURANT speeds up the simulation, but decreases accuracy */ +/* For similar wave forms, COURANT^2*GAMMA should be kept constant */ + +#define ADD_OSCILLATING_SOURCE 1 /* set to 1 to add an oscillating wave source */ +#define OSCILLATING_SOURCE_PERIOD 50 /* period of oscillating source */ + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 2 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 1100 /* number of frames of movie */ +#define NVID 10 /* number of iterations between images displayed on screen */ +#define NSEG 1000 /* number of segments of boundary */ +#define INITIAL_TIME 0 /* time after which to start saving frames */ +#define BOUNDARY_WIDTH 2 /* width of billiard boundary */ +#define PRINT_SPEED 0 /* print speed of moving source */ + +#define PAUSE 200 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Parameters of initial condition */ + +#define INITIAL_AMP 0.75 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.01 /* wavelength of initial condition */ + +/* Plot type, see list in global_pdes.c */ + +#define PLOT 1 + +#define PLOT_B 4 /* plot type for second movie */ + +/* Color schemes */ + +#define COLOR_PALETTE 12 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 13 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_pdes.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 0.5 /* sensitivity of color on wave amplitude */ +#define PHASE_FACTOR 1.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define E_SCALE 125.0 /* scaling factor for energy representation */ +#define LOG_SCALE 1.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 /* shift of colors on log scale */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 180.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -180.0 /* amplitude of variation of hue for color scheme C_HUE */ + +#define DRAW_COLOR_SCHEME 0 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 3.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 3.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +#define SAVE_TIME_SERIES 0 /* set to 1 to save wave time series at a point */ + +/* For debugging purposes only */ +#define FLOOR 0 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ + +``` + +### 6 October 22 - Phase space representation of parabolic resonators ### + +**Program:** `billiard_phase_space.c` + +**In function `animation()`:** `lyap_exponents[i] = draw_phase_portrait(16, 20, 100, 20, 0.2);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define XPHASEMAX 0.0 /* max x coordinate of phase portrait */ + +#define PIXELIZE 1 /* set to 1 to pixelize phase portrait (beta) */ +#define NGRID 200 /* size of grid to draw orbits with positive Lyapunov exponent */ + +#define SCALING_FACTOR 1.0 /* scaling factor of drawing, needed for flower billiards, otherwise set to 1.0 */ + +/* Choice of the billiard table, see global_particles.c */ + +#define B_DOMAIN 15 /* choice of domain shape */ + +#define CIRCLE_PATTERN 6 /* pattern of circles */ +#define POLYLINE_PATTERN 4 /* pattern of polyline */ + +#define ABSORBING_CIRCLES 1 /* set to 1 for circular scatterers to be absorbing */ + +#define NMAXCIRCLES 50000 /* total number of circles (must be at least NCX*NCY for square grid) */ +#define NMAXPOLY 50000 /* total number of sides of polygonal line */ +#define NCX 9 /* number of circles in x direction */ +#define NCY 20 /* number of circles in y direction */ +#define NPOISSON 500 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define NGOLDENSPIRAL 2000 /* max number of points for C_GOLDEN_SPIRAL arrandement */ +#define SDEPTH 2 /* Sierpinski gastket depth */ + +#define LAMBDA 0.0 /* parameter controlling shape of domain */ +#define MU 1.0 /* second parameter controlling shape of billiard */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NPOLY 4 /* number of sides of polygon */ +#define APOLY -1.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define DRAW_BILLIARD 1 /* set to 1 to draw billiard */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw additional construction lines for billiard */ +#define PERIODIC_BC 0 /* set to 1 to enforce periodic boundary conditions when drawing particles */ +#define PENROSE_RATIO 2.5 /* parameter controlling the shape of small ellipses in Penrose room */ + +#define RESAMPLE 0 /* set to 1 if particles should be added when dispersion too large */ +#define DEBUG 0 /* draw trajectories, for debugging purposes */ + +/* Simulation parameters */ + +#define NPART 1 /* number of particles */ +#define NPARTMAX 100000 /* maximal number of particles after resampling */ +#define TRAJ_LENGTH 10000 /* length of trajectory */ +#define LMAX 0.01 /* minimal segment length triggering resampling */ +#define DMIN 0.02 /* minimal distance to boundary for triggering resampling */ +#define CYCLE 1 /* set to 1 for closed curve (start in all directions) */ +#define SHOWTRAILS 0 /* set to 1 to keep trails of the particles */ +#define SHOWZOOM 0 /* set to 1 to show zoom on specific area */ +#define TEST_ACTIVE 1 /* set to 1 to test whether particle is in billiard */ +#define PRINT_TRAJECTORY_LENGTH 0 /* set to 1 to print length of trajectory 0 */ +#define PRINT_TRAJECTORY_PERIOD 0 /* set to 1 to print period of trajectory 0 */ +#define DRAW_LENGTHS_PLOT 0 /* set to 1 to plot trajectory lengths */ +#define LENGTHS_LOG_SCALE 1 /* set to 1 to use log scale for plot of lengths */ +#define MAX_ANGLE 90.0 /* range of angles of trajectory */ + +#define NSTEPS 3200 /* number of frames of movie */ +// #define NSTEPS 500 /* number of frames of movie */ +#define TIME 2500 /* time between movie frames, for fluidity of real-time simulation */ +#define DPHI 0.00001 /* integration step */ +#define NVID 150 /* number of iterations between images displayed on screen */ +#define SYMMETRIC_PARAMETER 1 /* set to 1 if parameters depend symmetrically on time */ + +/* Decreasing TIME accelerates the animation and the movie */ +/* For constant speed of movie, TIME*DPHI should be kept constant */ +/* However, increasing DPHI too much deterioriates quality of simulation */ +/* NVID tells how often a picture is drawn in the animation, increase it for faster anim */ +/* For a good quality movie, take for instance TIME = 400, DPHI = 0.00005, NVID = 100 */ + +/* Colors and other graphical parameters */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_pdes.c */ + +#define NCOLORS 64 /* number of colors */ +#define CFACTOR 3 /* color step */ +#define COLORSHIFT 0 /* hue of initial color */ +#define LYAP_PLOT_COLOR 200.0 /* color hue of Lyapunov exponent plot */ +#define RAINBOW_COLOR 0 /* set to 1 to use different colors for all particles */ +#define FLOWER_COLOR 0 /* set to 1 to adapt initial colors to flower billiard (tracks vs core) */ +#define NSEG 100 /* number of segments of boundary */ +#define LENGTH 0.03 /* length of velocity vectors */ +#define BILLIARD_WIDTH 2 /* width of billiard */ +#define PARTICLE_WIDTH 2 /* width of particles */ +#define FRONT_WIDTH 3 /* width of wave front */ + +#define BLACK 1 /* set to 1 for black background */ +#define COLOR_OUTSIDE 0 /* set to 1 for colored outside */ +#define OUTER_COLOR 270.0 /* color outside billiard */ +#define PAINT_INT 0 /* set to 1 to paint interior in other color (for polygon/Reuleaux) */ +#define PAINT_EXT 1 /* set to 1 to paint exterior */ + +#define PRINT_LAMBDA 1 /* set to 1 to print value of lambda */ +#define PRINT_MU 0 /* set to 1 to print value of mu */ +#define PRINT_LYAPUNOV 1 /* set to 1 to print mean Lyapunov exponent */ +#define PLOT_LYAPUNOV 1 /* set to 1 to add plot of Lyapunov exponents */ +#define LOGSCALEX_LYAP 0 /* set to 1 to use log scale on parameter axis of Lyapunov exponents */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define END_FRAMES 100 /* number of frames at end of movie */ + +``` + +### 5 October 22 - Solving a maze by shooting particles at it ### + +**Program:** `particle_billiard.c` + +**Initial condition in function `animation()`:** `init_drop_config(-1.3, 0.2, -0.25*PI, 0.25*PI, configs);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define SCALING_FACTOR 1.0 /* scaling factor of drawing, needed for flower billiards, otherwise set to 1.0 */ + +/* Choice of the billiard table, see global_particles.c */ + +#define B_DOMAIN 30 /* choice of domain shape */ + +#define CIRCLE_PATTERN 1 /* pattern of circles */ +#define POLYLINE_PATTERN 10 /* pattern of polyline */ + +#define ABSORBING_CIRCLES 1 /* set to 1 for circular scatterers to be absorbing */ + +#define NMAXCIRCLES 100000 /* total number of circles (must be at least NCX*NCY for square grid) */ +#define NMAXPOLY 100000 /* total number of sides of polygonal line */ +#define NCX 30 /* number of circles in x direction */ +#define NCY 20 /* number of circles in y direction */ +#define NPOISSON 500 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define NGOLDENSPIRAL 2000 /* max number of points for C_GOLDEN_SPIRAL arrandement */ +#define SDEPTH 1 /* Sierpinski gastket depth */ + +#define LAMBDA 1.5 /* parameter controlling shape of domain */ +#define MU 0.5 /* second parameter controlling shape of billiard */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NPOLY 6 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define PENROSE_RATIO 2.5 /* parameter controlling the shape of small ellipses in Penrose room */ + +#define DRAW_BILLIARD 1 /* set to 1 to draw billiard */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw additional construction lines for billiard */ +#define PERIODIC_BC 0 /* set to 1 to enforce periodic boundary conditions when drawing particles */ + +#define RESAMPLE 0 /* set to 1 if particles should be added when dispersion too large */ +#define DEBUG 0 /* draw trajectories, for debugging purposes */ + +/* Simulation parameters */ + +#define NPART 1000 /* number of particles */ +#define NPARTMAX 100000 /* maximal number of particles after resampling */ +#define LMAX 0.01 /* minimal segment length triggering resampling */ +#define DMIN 0.02 /* minimal distance to boundary for triggering resampling */ +#define CYCLE 1 /* set to 1 for closed curve (start in all directions) */ +#define SHOWTRAILS 0 /* set to 1 to keep trails of the particles */ +#define SHOWZOOM 0 /* set to 1 to show zoom on specific area */ +#define PRINT_PARTICLE_NUMBER 0 /* set to 1 to print number of particles */ +#define PRINT_LEFT_RIGHT_PARTICLE_NUMBER 1 /* set to 1 to print number of particles on left and right side */ +#define PRINT_COLLISION_NUMBER 0 /* set to 1 to print number of collisions */ +#define TEST_ACTIVE 1 /* set to 1 to test whether particle is in billiard */ + +#define NSTEPS 7000 /* number of frames of movie */ +#define TIME 1500 /* time between movie frames, for fluidity of real-time simulation */ +#define DPHI 0.00002 /* integration step */ +#define NVID 25 /* number of iterations between images displayed on screen */ +#define END_FRAMES 25 /* number of still frames at the end of the movie */ + +/* Decreasing TIME accelerates the animation and the movie */ +/* For constant speed of movie, TIME*DPHI should be kept constant */ +/* However, increasing DPHI too much deterioriates quality of simulation */ +/* NVID tells how often a picture is drawn in the animation, increase it for faster anim */ +/* For a good quality movie, take for instance TIME = 400, DPHI = 0.00005, NVID = 100 */ + +/* Colors and other graphical parameters */ + +#define COLOR_PALETTE 16 /* Color palette, see list in global_pdes.c */ + +#define NCOLORS 16 /* number of colors */ +#define COLORSHIFT 0 /* hue of initial color */ +#define RAINBOW_COLOR 1 /* set to 1 to use different colors for all particles */ +#define FLOWER_COLOR 0 /* set to 1 to adapt initial colors to flower billiard (tracks vs core) */ +#define NSEG 100 /* number of segments of boundary */ +#define LENGTH 0.04 /* length of velocity vectors */ +#define BILLIARD_WIDTH 3 /* width of billiard */ +#define PARTICLE_WIDTH 3 /* width of particles */ +#define FRONT_WIDTH 3 /* width of wave front */ + +#define BLACK 1 /* set to 1 for black background */ +#define COLOR_OUTSIDE 0 /* set to 1 for colored outside */ +#define OUTER_COLOR 270.0 /* color outside billiard */ +#define PAINT_INT 0 /* set to 1 to paint interior in other color (for polygon/Reuleaux) */ +#define PAINT_EXT 1 /* set to 1 to paint exterior */ + +#define PAUSE 200 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ + +#define NXMAZE 8 /* width of maze */ +#define NYMAZE 8 /* height of maze */ +#define MAZE_MAX_NGBH 4 /* max number of neighbours of maze cell */ +#define RAND_SHIFT 58 /* seed of random number generator */ +#define MAZE_XSHIFT 0.0 /* horizontal shift of maze */ + +``` + +### 4 October 22 - Just another sim in the hall: A breaking dam made of interacting bricks ### + +**Program:** `lennardjones.c` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 0 /* set to 1 to produce movies for wave height and energy simultaneously */ + +#define TIME_LAPSE 1 /* set to 1 to add a time-lapse movie at the end */ + /* so far incompatible with double movie */ +#define TIME_LAPSE_FACTOR 3 /* factor of time-lapse movie */ +#define TIME_LAPSE_FIRST 1 /* set to 1 to show time-lapse version first */ + +/* General geometrical parameters */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define INITXMIN -2.0 +#define INITXMAX -0.04 /* x interval for initial condition */ +#define INITYMIN -1.125 +#define INITYMAX 0.65 /* y interval for initial condition */ + +#define BCXMIN -2.05 +#define BCXMAX 2.0 /* x interval for boundary condition */ +#define BCYMIN -1.125 +#define BCYMAX 1.25 /* y interval for boundary condition */ + +#define OBSXMIN -2.0 +#define OBSXMAX 2.0 /* x interval for motion of obstacle */ + +#define CIRCLE_PATTERN 1 /* pattern of circles, see list in global_ljones.c */ + +#define ADD_FIXED_OBSTACLES 0 /* set to 1 do add fixed circular obstacles */ +#define OBSTACLE_PATTERN 3 /* pattern of obstacles, see list in global_ljones.c */ + +#define ADD_FIXED_SEGMENTS 1 /* set to 1 to add fixed segments as obstacles */ +#define SEGMENT_PATTERN 17 /* pattern of repelling segments, see list in global_ljones.c */ +#define ROCKET_SHAPE 0 /* shape of rocket combustion chamber, see list in global_ljones.c */ +#define ROCKET_SHAPE_B 0 /* shape of second rocket */ +#define NOZZLE_SHAPE 1 /* shape of nozzle, see list in global_ljones.c */ +#define NOZZLE_SHAPE_B 4 /* shape of nozzle for second rocket, see list in global_ljones.c */ + +#define TWO_TYPES 0 /* set to 1 to have two types of particles */ +#define TPYE_PROPORTION 0.5 /* proportion of particles of first type */ +#define SYMMETRIZE_FORCE 1 /* set to 1 to symmetrize two-particle interaction, only needed if particles are not all the same */ +#define CENTER_PX 0 /* set to 1 to center horizontal momentum */ +#define CENTER_PY 0 /* set to 1 to center vertical momentum */ +#define CENTER_PANGLE 0 /* set to 1 to center angular momentum */ + +#define INTERACTION 1 /* particle interaction, see list in global_ljones.c */ +#define INTERACTION_B 1 /* particle interaction for second type of particle, see list in global_ljones.c */ +#define SPIN_INTER_FREQUENCY 5.0 /* angular frequency of spin-spin interaction */ +#define SPIN_INTER_FREQUENCY_B 2.0 /* angular frequency of spin-spin interaction for second particle type */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 100 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define PDISC_DISTANCE 2.5 /* minimal distance in Poisson disc process, controls density of particles */ +#define PDISC_CANDIDATES 100 /* number of candidates in construction of Poisson disc process */ +#define RANDOM_POLY_ANGLE 0 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.8 /* parameter controlling the dimensions of domain */ +#define MU 0.0075 /* parameter controlling radius of particles */ +#define MU_B 0.018 /* parameter controlling radius of particles of second type */ +#define NPOLY 25 /* number of sides of polygon */ +#define APOLY 0.666666666 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 4 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 90 /* number of grid point for grid of disks */ +#define NGRIDY 100 /* number of grid point for grid of disks */ +#define EHRENFEST_RADIUS 0.9 /* radius of container for Ehrenfest urn configuration */ +#define EHRENFEST_WIDTH 0.035 /* width of tube for Ehrenfest urn configuration */ +#define TWO_CIRCLES_RADIUS_RATIO 0.8 /* ratio of radii for S_TWO_CIRCLES_EXT segment configuration */ +#define DAM_WIDTH 0.05 /* width of dam for S_DAM segment configuration */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 2400 /* number of frames of movie */ +#define NVID 60 /* number of iterations between images displayed on screen */ +#define NSEG 250 /* number of segments of boundary */ +#define INITIAL_TIME 150 /* time after which to start saving frames */ +#define OBSTACLE_INITIAL_TIME 400 /* time after which to start moving obstacle */ +#define BOUNDARY_WIDTH 1 /* width of particle boundary */ +#define LINK_WIDTH 2 /* width of links between particles */ +#define CONTAINER_WIDTH 4 /* width of container boundary */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ + +/* Boundary conditions, see list in global_ljones.c */ + +#define BOUNDARY_COND 0 + +/* Plot type, see list in global_ljones.c */ + +#define PLOT 11 +#define PLOT_B 11 /* plot type for second movie */ + +#define DRAW_BONDS 0 /* set to 1 to draw bonds between neighbours */ +#define COLOR_BONDS 1 /* set to 1 to color bonds according to length */ +#define FILL_TRIANGLES 0 /* set to 1 to fill triangles between neighbours */ + +/* Color schemes */ + +#define COLOR_PALETTE 10 /* Color palette, see list in global_ljones.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_ljones.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 0.5 /* sensitivity of color on wave amplitude */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 220.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -50.0 /* amplitude of variation of hue for color scheme C_HUE */ + +/* particle properties */ + +#define ENERGY_HUE_MIN 330.0 /* color of original particle */ +#define ENERGY_HUE_MAX 50.0 /* color of saturated particle */ +#define PARTICLE_HUE_MIN 359.0 /* color of original particle */ +#define PARTICLE_HUE_MAX 0.0 /* color of saturated particle */ +#define PARTICLE_EMAX 2.0e2 /* energy of particle with hottest color */ +#define HUE_TYPE0 70.0 /* hue of particles of type 0 */ +#define HUE_TYPE1 280.0 /* hue of particles of type 1 */ +#define HUE_TYPE2 .0 /* hue of particles of type 2 */ +#define HUE_TYPE3 210.0 /* hue of particles of type 3 */ + +#define RANDOM_RADIUS 0 /* set to 1 for random circle radius */ +#define DT_PARTICLE 3.0e-6 /* time step for particle displacement */ +#define KREPEL 12.0 /* constant in repelling force between particles */ +#define EQUILIBRIUM_DIST 3.5 /* Lennard-Jones equilibrium distance */ +#define EQUILIBRIUM_DIST_B 3.5 /* Lennard-Jones equilibrium distance for second type of particle */ +#define REPEL_RADIUS 20.0 /* radius in which repelling force acts (in units of particle radius) */ +#define DAMPING 50.0 /* damping coefficient of particles */ +#define PARTICLE_MASS 1.0 /* mass of particle of radius MU */ +#define PARTICLE_MASS_B 1.0 /* mass of particle of radius MU */ +#define PARTICLE_INERTIA_MOMENT 0.2 /* moment of inertia of particle */ +#define PARTICLE_INERTIA_MOMENT_B 0.02 /* moment of inertia of second type of particle */ +#define V_INITIAL 0.0 /* initial velocity range */ +#define OMEGA_INITIAL 10.0 /* initial angular velocity range */ + +#define THERMOSTAT 1 /* set to 1 to switch on thermostat */ +#define VARY_THERMOSTAT 0 /* set to 1 for time-dependent thermostat schedule */ +#define SIGMA 5.0 /* noise intensity in thermostat */ +#define BETA 0.003 /* initial inverse temperature */ +#define MU_XI 0.01 /* friction constant in thermostat */ +#define KSPRING_BOUNDARY 1.0e11 /* confining harmonic potential outside simulation region */ +#define KSPRING_OBSTACLE 1.0e11 /* harmonic potential of obstacles */ +#define NBH_DIST_FACTOR 7.5 /* radius in which to count neighbours */ +#define GRAVITY 2000.0 /* gravity acting on all particles */ +#define GRAVITY_X 0.0 /* horizontal gravity acting on all particles */ +#define INCREASE_GRAVITY 0 /* set to 1 to increase gravity during the simulation */ +#define GRAVITY_SCHEDULE 2 /* type of gravity schedule, see list in global_ljones.c */ +#define GRAVITY_FACTOR 100.0 /* factor by which to increase gravity */ +#define GRAVITY_INITIAL_TIME 200 /* time at start of simulation with constant gravity */ +#define GRAVITY_RESTORE_TIME 700 /* time at end of simulation with gravity restored to initial value */ + +#define ROTATION 0 /* set to 1 to include rotation of particles */ +#define COUPLE_ANGLE_TO_THERMOSTAT 0 /* set to 1 to couple angular degrees of freedom to thermostat */ +#define DIMENSION_FACTOR 1.0 /* scaling factor taking into account number of degrees of freedom */ +#define KTORQUE 100.0 /* force constant in angular dynamics */ +#define KTORQUE_B 10.0 /* force constant in angular dynamics */ +#define KTORQUE_DIFF 150.0 /* force constant in angular dynamics for different particles */ +#define DRAW_SPIN 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_SPIN_B 0 /* set to 1 to draw spin vectors of particles */ +#define DRAW_CROSS 1 /* set to 1 to draw cross on particles of second type */ +#define SPIN_RANGE 7.0 /* range of spin-spin interaction */ +#define SPIN_RANGE_B 5.0 /* range of spin-spin interaction for second type of particle */ +#define QUADRUPOLE_RATIO 0.6 /* anisotropy in quadrupole potential */ + +#define INCREASE_BETA 0 /* set to 1 to increase BETA during simulation */ +#define BETA_FACTOR 0.1 /* factor by which to change BETA during simulation */ +#define N_TOSCILLATIONS 1.5 /* number of temperature oscillations in BETA schedule */ +#define NO_OSCILLATION 1 /* set to 1 to have exponential BETA change only */ +#define MIDDLE_CONSTANT_PHASE 3000 /* final phase in which temperature is constant */ +#define FINAL_DECREASE_PHASE -1 /* final phase in which temperature decreases */ +#define FINAL_CONSTANT_PHASE -1 /* final phase in which temperature is constant */ + +#define DECREASE_CONTAINER_SIZE 0 /* set to 1 to decrease size of container */ +#define SYMMETRIC_DECREASE 0 /* set tp 1 to decrease container symmetrically */ +#define COMPRESSION_RATIO 0.3 /* final size of container */ +#define RESTORE_CONTAINER_SIZE 1 /* set to 1 to restore container to initial size at end of simulation */ +#define RESTORE_TIME 700 /* time before end of sim at which to restore size */ + +#define MOVE_OBSTACLE 0 /* set to 1 to have a moving obstacle */ +#define CENTER_VIEW_ON_OBSTACLE 0 /* set to 1 to center display on moving obstacle */ +#define RESAMPLE_Y 0 /* set to 1 to resample y coordinate of moved particles (for shock waves) */ +#define NTRIALS 2000 /* number of trials when resampling */ +#define OBSTACLE_RADIUS 0.12 /* radius of obstacle for circle boundary conditions */ +#define FUNNEL_WIDTH 0.25 /* funnel width for funnel boundary conditions */ +#define OBSTACLE_XMIN 0.0 /* initial position of obstacle */ +#define OBSTACLE_XMAX 3.0 /* final position of obstacle */ +#define RECORD_PRESSURES 0 /* set to 1 to record pressures on obstacle */ +#define N_PRESSURES 100 /* number of intervals to record pressure */ +#define N_P_AVERAGE 100 /* size of pressure averaging window */ +#define N_T_AVERAGE 50 /* size of temperature averaging window */ +#define MAX_PRESSURE 3.0e10 /* pressure shown in "hottest" color */ +#define PARTIAL_THERMO_COUPLING 0 /* set to 1 to couple only particles to the right of obstacle to thermostat */ +#define PARTIAL_THERMO_REGION 1 /* region for partial thermostat coupling (see list in global_ljones.c) */ +#define PARTIAL_THERMO_SHIFT 0.2 /* distance from obstacle at the right of which particles are coupled to thermostat */ +#define PARTIAL_THERMO_WIDTH 0.5 /* vertical size of partial thermostat coupling */ +#define PARTIAL_THERMO_HEIGHT 0.2 /* vertical size of partial thermostat coupling */ + +#define INCREASE_KREPEL 0 /* set to 1 to increase KREPEL during simulation */ +#define KREPEL_FACTOR 1000.0 /* factor by which to change KREPEL during simulation */ + +#define PART_AT_BOTTOM 0 /* set to 1 to include "seed" particles at bottom */ +#define MASS_PART_BOTTOM 10000.0 /* mass of particles at bottom */ +#define NPART_BOTTOM 100 /* number of particles at the bottom */ + +#define ADD_PARTICLES 0 /* set to 1 to add particles */ +#define ADD_TIME 0 /* time at which to add first particle */ +#define ADD_PERIOD 10000 /* time interval between adding further particles */ +#define FINAL_NOADD_PERIOD 200 /* final period where no particles are added */ +#define SAFETY_FACTOR 2.0 /* no particles are added at distance less than MU*SAFETY_FACTOR of other particles */ + +#define TRACER_PARTICLE 0 /* set to 1 to have a tracer particle */ +#define N_TRACER_PARTICLES 3 /* number of tracer particles */ +#define TRAJECTORY_LENGTH 8000 /* length of recorded trajectory */ +#define TRACER_PARTICLE_MASS 4.0 /* relative mass of tracer particle */ +#define TRAJECTORY_WIDTH 3 /* width of tracer particle trajectory */ + +#define ROTATE_BOUNDARY 0 /* set to 1 to rotate the repelling segments */ +#define SMOOTH_ROTATION 1 /* set to 1 to update segments at each time step (rather than at each movie frame) */ +#define PERIOD_ROTATE_BOUNDARY 1000 /* period of rotating boundary */ +#define ROTATE_INITIAL_TIME 0 /* initial time without rotation */ +#define ROTATE_FINAL_TIME 100 /* final time without rotation */ +#define ROTATE_CHANGE_TIME 0.33 /* relative duration of acceleration/deceleration phases */ +#define OMEGAMAX 100.0 /* maximal rotation speed */ +#define PRINT_OMEGA 0 /* set to 1 to print angular speed */ +#define PRINT_PARTICLE_SPEEDS 0 /* set to 1 to print average speeds/momenta of particles */ +#define PRINT_SEGMENTS_SPEEDS 0 /* set to 1 to print velocity of moving segments */ + +#define MOVE_BOUNDARY 0 /* set to 1 to move repelling segments, due to force from particles */ +#define SEGMENTS_MASS 40.0 /* mass of collection of segments */ +#define DEACTIVATE_SEGMENT 1 /* set to 1 to deactivate last segment after a certain time */ +#define SEGMENT_DEACTIVATION_TIME 200 /* time at which to deactivate last segment */ +#define RELEASE_ROCKET_AT_DEACTIVATION 1 /* set to 1 to limit segments velocity before segment release */ +#define SEGMENTS_X0 0.0 /* initial position of segments */ +#define SEGMENTS_Y0 0.0 /* initial position of segments */ +#define SEGMENTS_VX0 0.0 /* initial velocity of segments */ +#define SEGMENTS_VY0 0.0 /* initial velocity of segments */ +#define DAMP_SEGS_AT_NEGATIVE_Y 0 /* set to 1 to dampen segments when y coordinate is negative */ + +#define MOVE_SEGMENT_GROUPS 1 /* set to 1 to group segments into moving units */ +#define SEGMENT_GROUP_MASS 100.0 /* mass of segment group */ +#define SEGMENT_GROUP_I 15.0 /* moment of inertia of segment group */ +#define SEGMENT_GROUP_DAMPING 50.0 /* damping of segment groups */ +#define GROUP_REPULSION 1 /* set to 1 for groups of segments to repel each other */ +#define KSPRING_GROUPS 1.0e8 /* harmonic potential between segment groups */ +#define GROUP_WIDTH 0.05 /* interaction width of groups */ +#define GROUP_G_REPEL 1 /* set to 1 to add repulsion between centers of mass of groups */ +#define GROUP_G_REPEL_RADIUS 0.12 /* radius within which centers of mass of groups repel each other */ + +#define POSITION_DEPENDENT_TYPE 0 /* set to 1 to make particle type depend on initial position */ +#define POSITION_Y_DEPENDENCE 0 /* set to 1 for the separation between particles to be horizontal */ +#define PRINT_ENTROPY 0 /* set to 1 to compute entropy */ + +#define REACTION_DIFFUSION 0 /* set to 1 to simulate a chemical reaction (particles may change type) */ +#define RD_TYPES 3 /* number of types in reaction-diffusion equation */ +#define REACTION_PROB 0.0045 /* probability controlling reaction term */ + +#define PRINT_PARTICLE_NUMBER 0 /* set to 1 to print total number of particles */ +#define PRINT_LEFT 1 /* set to 1 to print certain parameters at the top left instead of right */ +#define PLOT_SPEEDS 0 /* set to 1 to add a plot of obstacle speeds (e.g. for rockets) */ +#define VMAX_PLOT_SPEEDS 5.0 /* vertical scale of plot of obstacle speeds */ + +#define EHRENFEST_COPY 0 /* set to 1 to add equal number of larger particles (for Ehrenfest model) */ + +#define LID_MASS 1000.0 /* mass of lid for BC_RECTANGLE_LID b.c. */ +#define LID_WIDTH 0.1 /* width of lid for BC_RECTANGLE_LID b.c. */ +#define WALL_MASS 2000.0 /* mass of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_FRICTION 0.0 /* friction on wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_WIDTH 0.1 /* width of wall for BC_RECTANGLE_WALL b.c. */ +#define WALL_VMAX 100.0 /* max speed of wall */ +#define WALL_TIME 0 /* time during which to keep wall */ + +#define FLOOR_FORCE 1 /* set to 1 to limit force on particle to FMAX */ +#define FMAX 1.0e12 /* maximal force */ +#define FLOOR_OMEGA 0 /* set to 1 to limit particle momentum to PMAX */ +#define PMAX 1000.0 /* maximal force */ + +#define HASHX 160 /* size of hashgrid in x direction */ +#define HASHY 80 /* size of hashgrid in y direction */ +#define HASHMAX 100 /* maximal number of particles per hashgrid cell */ +#define HASHGRID_PADDING 0.1 /* padding of hashgrid outside simulation window */ + +#define DRAW_COLOR_SCHEME 0 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 8.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 12.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +``` + +### 3 October 22 - Total internal reflection, with an index of refraction of 1.33 ### + +**Program:** `wave_billiard.c` + +**Initial condition in function `animation()`:** `init_circular_wave(-1.2, -0.5, phi, psi, xy_in);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ +#define DOUBLE_MOVIE 1 /* set to 1 to produce movies for wave height and energy simultaneously */ + +/* General geometrical parameters */ + +#define WINWIDTH 1920 /* window width */ +#define WINHEIGHT 1000 /* window height */ +#define NX 3840 /* number of grid points on x axis */ +#define NY 2000 /* number of grid points on y axis */ + +#define XMIN -1.9 +#define XMAX 2.1 /* x interval */ +#define YMIN -1.041666667 +#define YMAX 1.041666667 /* y interval for 9/16 aspect ratio */ + +#define HIGHRES 1 /* set to 1 if resolution of grid is double that of displayed image */ + +#define JULIA_SCALE 1.0 /* scaling for Julia sets */ + +/* Choice of the billiard table */ + +#define B_DOMAIN 6 /* choice of domain shape, see list in global_pdes.c */ + +#define CIRCLE_PATTERN 1 /* pattern of circles or polygons, see list in global_pdes.c */ + +#define COMPARISON 0 /* set to 1 to compare two different patterns (beta) */ +#define B_DOMAIN_B 20 /* second domain shape, for comparisons */ +#define CIRCLE_PATTERN_B 0 /* second pattern of circles or polygons */ + +#define P_PERCOL 0.25 /* probability of having a circle in C_RAND_PERCOL arrangement */ +#define NPOISSON 300 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define RANDOM_POLY_ANGLE 1 /* set to 1 to randomize angle of polygons */ + +#define LAMBDA 0.0 /* parameter controlling the dimensions of domain */ +#define MU 0.3 /* parameter controlling the dimensions of domain */ +#define NPOLY 6 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define MDEPTH 6 /* depth of computation of Menger gasket */ +#define MRATIO 3 /* ratio defining Menger gasket */ +#define MANDELLEVEL 1000 /* iteration level for Mandelbrot set */ +#define MANDELLIMIT 10.0 /* limit value for approximation of Mandelbrot set */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NGRIDX 12 /* number of grid point for grid of disks */ +#define NGRIDY 15 /* number of grid point for grid of disks */ + +#define X_SHOOTER -0.2 +#define Y_SHOOTER -0.6 +#define X_TARGET 0.4 +#define Y_TARGET 0.7 /* shooter and target positions in laser fight */ + +#define ISO_XSHIFT_LEFT -2.9 +#define ISO_XSHIFT_RIGHT 1.4 +#define ISO_YSHIFT_LEFT -0.15 +#define ISO_YSHIFT_RIGHT -0.15 +#define ISO_SCALE 0.5 /* coordinates for isospectral billiards */ + +/* You can add more billiard tables by adapting the functions */ +/* xy_in_billiard and draw_billiard below */ + +/* Physical parameters of wave equation */ + +#define TWOSPEEDS 1 /* set to 1 to replace hardcore boundary by medium with different speed */ +#define OSCILLATE_LEFT 0 /* set to 1 to add oscilating boundary condition on the left */ +#define OSCILLATE_TOPBOT 0 /* set to 1 to enforce a planar wave on top and bottom boundary */ +#define OSCILLATION_SCHEDULE 3 /* oscillation schedule, see list in global_pdes.c */ + +#define OMEGA 0.0005 /* frequency of periodic excitation */ +#define AMPLITUDE 0.8 /* amplitude of periodic excitation */ +#define ACHIRP 0.25 /* acceleration coefficient in chirp */ +#define DAMPING 0.0 /* damping of periodic excitation */ +#define COURANT 0.12 /* Courant number */ +#define COURANTB 0.09 /* Courant number in medium B */ +#define GAMMA 0.0 /* damping factor in wave equation */ +#define GAMMAB 0.0 /* damping factor in wave equation */ +#define GAMMA_SIDES 1.0e-4 /* damping factor on boundary */ +#define GAMMA_TOPBOT 1.0e-7 /* damping factor on boundary */ +#define KAPPA 0.0 /* "elasticity" term enforcing oscillations */ +#define KAPPA_SIDES 5.0e-4 /* "elasticity" term on absorbing boundary */ +#define KAPPA_TOPBOT 0.0 /* "elasticity" term on absorbing boundary */ +/* The Courant number is given by c*DT/DX, where DT is the time step and DX the lattice spacing */ +/* The physical damping coefficient is given by GAMMA/(DT)^2 */ +/* Increasing COURANT speeds up the simulation, but decreases accuracy */ +/* For similar wave forms, COURANT^2*GAMMA should be kept constant */ + +#define ADD_OSCILLATING_SOURCE 1 /* set to 1 to add an oscillating wave source */ +#define OSCILLATING_SOURCE_PERIOD 50 /* period of oscillating source */ + +/* Boundary conditions, see list in global_pdes.c */ + +#define B_COND 2 + +/* Parameters for length and speed of simulation */ + +#define NSTEPS 1500 /* number of frames of movie */ +#define NVID 10 /* number of iterations between images displayed on screen */ +#define NSEG 1000 /* number of segments of boundary */ +#define INITIAL_TIME 0 /* time after which to start saving frames */ +#define BOUNDARY_WIDTH 2 /* width of billiard boundary */ +#define PRINT_SPEED 0 /* print speed of moving source */ + +#define PAUSE 200 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define MID_FRAMES 20 /* number of still frames between parts of two-part movie */ +#define END_FRAMES 100 /* number of still frames at end of movie */ +#define FADE 1 /* set to 1 to fade at end of movie */ + +/* Parameters of initial condition */ + +#define INITIAL_AMP 0.75 /* amplitude of initial condition */ +#define INITIAL_VARIANCE 0.0002 /* variance of initial condition */ +#define INITIAL_WAVELENGTH 0.01 /* wavelength of initial condition */ + +/* Plot type, see list in global_pdes.c */ + +#define PLOT 0 + +#define PLOT_B 4 /* plot type for second movie */ + +/* Color schemes */ + +#define COLOR_PALETTE 11 /* Color palette, see list in global_pdes.c */ +#define COLOR_PALETTE_B 13 /* Color palette, see list in global_pdes.c */ + +#define BLACK 1 /* background */ + +#define COLOR_SCHEME 3 /* choice of color scheme, see list in global_pdes.c */ + +#define SCALE 0 /* set to 1 to adjust color scheme to variance of field */ +#define SLOPE 0.5 /* sensitivity of color on wave amplitude */ +#define PHASE_FACTOR 1.0 /* factor in computation of phase in color scheme P_3D_PHASE */ +#define PHASE_SHIFT 0.0 /* shift of phase in color scheme P_3D_PHASE */ +#define ATTENUATION 0.0 /* exponential attenuation coefficient of contrast with time */ +#define E_SCALE 125.0 /* scaling factor for energy representation */ +#define LOG_SCALE 1.0 /* scaling factor for energy log representation */ +#define LOG_SHIFT 1.0 /* shift of colors on log scale */ +#define RESCALE_COLOR_IN_CENTER 0 /* set to 1 to decrease color intentiy in the center (for wave escaping ring) */ + +#define COLORHUE 260 /* initial hue of water color for scheme C_LUM */ +#define COLORDRIFT 0.0 /* how much the color hue drifts during the whole simulation */ +#define LUMMEAN 0.5 /* amplitude of luminosity variation for scheme C_LUM */ +#define LUMAMP 0.3 /* amplitude of luminosity variation for scheme C_LUM */ +#define HUEMEAN 180.0 /* mean value of hue for color scheme C_HUE */ +#define HUEAMP -180.0 /* amplitude of variation of hue for color scheme C_HUE */ + +#define DRAW_COLOR_SCHEME 1 /* set to 1 to plot the color scheme */ +#define COLORBAR_RANGE 3.0 /* scale of color scheme bar */ +#define COLORBAR_RANGE_B 3.0 /* scale of color scheme bar for 2nd part */ +#define ROTATE_COLOR_SCHEME 0 /* set to 1 to draw color scheme horizontally */ + +#define SAVE_TIME_SERIES 0 /* set to 1 to save wave time series at a point */ + +/* For debugging purposes only */ +#define FLOOR 0 /* set to 1 to limit wave amplitude to VMAX */ +#define VMAX 10.0 /* max value of wave amplitude */ + +``` + +### 2 October 22 - Phase space representation of billiards interpolating between a circle and a hexagon ### + +**Program:** `billiard_phase_space.c` + +**In function `animation()`:** `lyap_exponents[i] = draw_phase_portrait(12, 20, 100, 20, 0.2);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define XPHASEMAX 0.0 /* max x coordinate of phase portrait */ + +#define PIXELIZE 1 /* set to 1 to pixelize phase portrait (beta) */ +#define NGRID 200 /* size of grid to draw orbits with positive Lyapunov exponent */ + +#define SCALING_FACTOR 1.0 /* scaling factor of drawing, needed for flower billiards, otherwise set to 1.0 */ + +/* Choice of the billiard table, see global_particles.c */ + +#define B_DOMAIN 9 /* choice of domain shape */ + +#define CIRCLE_PATTERN 6 /* pattern of circles */ +#define POLYLINE_PATTERN 4 /* pattern of polyline */ + +#define ABSORBING_CIRCLES 1 /* set to 1 for circular scatterers to be absorbing */ + +#define NMAXCIRCLES 50000 /* total number of circles (must be at least NCX*NCY for square grid) */ +#define NMAXPOLY 50000 /* total number of sides of polygonal line */ +#define NCX 9 /* number of circles in x direction */ +#define NCY 20 /* number of circles in y direction */ +#define NPOISSON 500 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define NGOLDENSPIRAL 2000 /* max number of points for C_GOLDEN_SPIRAL arrandement */ +#define SDEPTH 2 /* Sierpinski gastket depth */ + +#define LAMBDA 1000.0 /* parameter controlling shape of domain */ +#define MU 1.0 /* second parameter controlling shape of billiard */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NPOLY 6 /* number of sides of polygon */ +#define APOLY -1.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define DRAW_BILLIARD 1 /* set to 1 to draw billiard */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw additional construction lines for billiard */ +#define PERIODIC_BC 0 /* set to 1 to enforce periodic boundary conditions when drawing particles */ +#define PENROSE_RATIO 2.5 /* parameter controlling the shape of small ellipses in Penrose room */ + +#define RESAMPLE 0 /* set to 1 if particles should be added when dispersion too large */ +#define DEBUG 0 /* draw trajectories, for debugging purposes */ + +/* Simulation parameters */ + +#define NPART 1 /* number of particles */ +#define NPARTMAX 100000 /* maximal number of particles after resampling */ +#define TRAJ_LENGTH 10000 /* length of trajectory */ +#define LMAX 0.01 /* minimal segment length triggering resampling */ +#define DMIN 0.02 /* minimal distance to boundary for triggering resampling */ +#define CYCLE 1 /* set to 1 for closed curve (start in all directions) */ +#define SHOWTRAILS 0 /* set to 1 to keep trails of the particles */ +#define SHOWZOOM 0 /* set to 1 to show zoom on specific area */ +#define TEST_ACTIVE 1 /* set to 1 to test whether particle is in billiard */ +#define PRINT_TRAJECTORY_LENGTH 0 /* set to 1 to print length of trajectory 0 */ +#define PRINT_TRAJECTORY_PERIOD 0 /* set to 1 to print period of trajectory 0 */ +#define DRAW_LENGTHS_PLOT 0 /* set to 1 to plot trajectory lengths */ +#define LENGTHS_LOG_SCALE 1 /* set to 1 to use log scale for plot of lengths */ +#define MAX_ANGLE 90.0 /* range of angles of trajectory */ + +#define NSTEPS 4000 /* number of frames of movie */ +#define TIME 2500 /* time between movie frames, for fluidity of real-time simulation */ +#define DPHI 0.00001 /* integration step */ +#define NVID 150 /* number of iterations between images displayed on screen */ +#define SYMMETRIC_PARAMETER 1 /* set to 1 if parameters depend symmetrically on time */ + +/* Decreasing TIME accelerates the animation and the movie */ +/* For constant speed of movie, TIME*DPHI should be kept constant */ +/* However, increasing DPHI too much deterioriates quality of simulation */ +/* NVID tells how often a picture is drawn in the animation, increase it for faster anim */ +/* For a good quality movie, take for instance TIME = 400, DPHI = 0.00005, NVID = 100 */ + +/* Colors and other graphical parameters */ + +#define COLOR_PALETTE 13 /* Color palette, see list in global_pdes.c */ + +#define NCOLORS 64 /* number of colors */ +#define CFACTOR 3 /* color step */ +#define COLORSHIFT 0 /* hue of initial color */ +#define LYAP_PLOT_COLOR 200.0 /* color hue of Lyapunov exponent plot */ +#define RAINBOW_COLOR 0 /* set to 1 to use different colors for all particles */ +#define FLOWER_COLOR 0 /* set to 1 to adapt initial colors to flower billiard (tracks vs core) */ +#define NSEG 100 /* number of segments of boundary */ +#define LENGTH 0.03 /* length of velocity vectors */ +#define BILLIARD_WIDTH 2 /* width of billiard */ +#define PARTICLE_WIDTH 2 /* width of particles */ +#define FRONT_WIDTH 3 /* width of wave front */ + +#define BLACK 1 /* set to 1 for black background */ +#define COLOR_OUTSIDE 0 /* set to 1 for colored outside */ +#define OUTER_COLOR 270.0 /* color outside billiard */ +#define PAINT_INT 0 /* set to 1 to paint interior in other color (for polygon/Reuleaux) */ +#define PAINT_EXT 1 /* set to 1 to paint exterior */ + +#define PRINT_LAMBDA 1 /* set to 1 to print value of lambda */ +#define PRINT_MU 0 /* set to 1 to print value of mu */ +#define PRINT_LYAPUNOV 1 /* set to 1 to print mean Lyapunov exponent */ +#define PLOT_LYAPUNOV 1 /* set to 1 to add plot of Lyapunov exponents */ + +#define PAUSE 1000 /* number of frames after which to pause */ +#define PSLEEP 1 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ +#define END_FRAMES 100 /* number of frames at end of movie */ + +``` + +### 1 October 22 - Solving a maze with laser beams ### + +**Program:** `particle_billiard.c` + +**Initial condition in function `animation()`:** `init_drop_config(-1.3, 0.2, -0.25*PI, 0.25*PI, configs);` + +``` +#define MOVIE 1 /* set to 1 to generate movie */ + +#define WINWIDTH 1280 /* window width */ +#define WINHEIGHT 720 /* window height */ + +#define XMIN -2.0 +#define XMAX 2.0 /* x interval */ +#define YMIN -1.125 +#define YMAX 1.125 /* y interval for 9/16 aspect ratio */ + +#define SCALING_FACTOR 1.0 /* scaling factor of drawing, needed for flower billiards, otherwise set to 1.0 */ + +/* Choice of the billiard table, see global_particles.c */ + +#define B_DOMAIN 30 /* choice of domain shape */ + +#define CIRCLE_PATTERN 1 /* pattern of circles */ +#define POLYLINE_PATTERN 10 /* pattern of polyline */ + +#define ABSORBING_CIRCLES 1 /* set to 1 for circular scatterers to be absorbing */ + +#define NMAXCIRCLES 100000 /* total number of circles (must be at least NCX*NCY for square grid) */ +#define NMAXPOLY 100000 /* total number of sides of polygonal line */ +#define NCX 30 /* number of circles in x direction */ +#define NCY 20 /* number of circles in y direction */ +#define NPOISSON 500 /* number of points for Poisson C_RAND_POISSON arrangement */ +#define NGOLDENSPIRAL 2000 /* max number of points for C_GOLDEN_SPIRAL arrandement */ +#define SDEPTH 1 /* Sierpinski gastket depth */ + +#define LAMBDA 1.5 /* parameter controlling shape of domain */ +#define MU 0.5 /* second parameter controlling shape of billiard */ +#define FOCI 1 /* set to 1 to draw focal points of ellipse */ +#define NPOLY 6 /* number of sides of polygon */ +#define APOLY 0.0 /* angle by which to turn polygon, in units of Pi/2 */ +#define PENROSE_RATIO 2.5 /* parameter controlling the shape of small ellipses in Penrose room */ + +#define DRAW_BILLIARD 1 /* set to 1 to draw billiard */ +#define DRAW_CONSTRUCTION_LINES 0 /* set to 1 to draw additional construction lines for billiard */ +#define PERIODIC_BC 0 /* set to 1 to enforce periodic boundary conditions when drawing particles */ + +#define RESAMPLE 0 /* set to 1 if particles should be added when dispersion too large */ +#define DEBUG 0 /* draw trajectories, for debugging purposes */ + +/* Simulation parameters */ + +#define NPART 1000 /* number of particles */ +#define NPARTMAX 100000 /* maximal number of particles after resampling */ +#define LMAX 0.01 /* minimal segment length triggering resampling */ +#define DMIN 0.02 /* minimal distance to boundary for triggering resampling */ +#define CYCLE 1 /* set to 1 for closed curve (start in all directions) */ +#define SHOWTRAILS 1 /* set to 1 to keep trails of the particles */ +#define SHOWZOOM 0 /* set to 1 to show zoom on specific area */ +#define PRINT_PARTICLE_NUMBER 1 /* set to 1 to print number of particles */ +#define PRINT_COLLISION_NUMBER 0 /* set to 1 to print number of collisions */ +#define TEST_ACTIVE 1 /* set to 1 to test whether particle is in billiard */ + +#define NSTEPS 5250 /* number of frames of movie */ +#define TIME 1500 /* time between movie frames, for fluidity of real-time simulation */ +#define DPHI 0.00002 /* integration step */ +#define NVID 25 /* number of iterations between images displayed on screen */ +#define END_FRAMES 25 /* number of still frames at the end of the movie */ + +/* Decreasing TIME accelerates the animation and the movie */ +/* For constant speed of movie, TIME*DPHI should be kept constant */ +/* However, increasing DPHI too much deterioriates quality of simulation */ +/* NVID tells how often a picture is drawn in the animation, increase it for faster anim */ +/* For a good quality movie, take for instance TIME = 400, DPHI = 0.00005, NVID = 100 */ + +/* Colors and other graphical parameters */ + +#define COLOR_PALETTE 11 /* Color palette, see list in global_pdes.c */ + +#define NCOLORS 16 /* number of colors */ +#define COLORSHIFT 0 /* hue of initial color */ +#define RAINBOW_COLOR 1 /* set to 1 to use different colors for all particles */ +#define FLOWER_COLOR 0 /* set to 1 to adapt initial colors to flower billiard (tracks vs core) */ +#define NSEG 100 /* number of segments of boundary */ +#define LENGTH 0.03 /* length of velocity vectors */ +#define BILLIARD_WIDTH 3 /* width of billiard */ +#define PARTICLE_WIDTH 3 /* width of particles */ +#define FRONT_WIDTH 3 /* width of wave front */ + +#define BLACK 1 /* set to 1 for black background */ +#define COLOR_OUTSIDE 0 /* set to 1 for colored outside */ +#define OUTER_COLOR 270.0 /* color outside billiard */ +#define PAINT_INT 0 /* set to 1 to paint interior in other color (for polygon/Reuleaux) */ +#define PAINT_EXT 1 /* set to 1 to paint exterior */ + +#define PAUSE 200 /* number of frames after which to pause */ +#define PSLEEP 2 /* sleep time during pause */ +#define SLEEP1 1 /* initial sleeping time */ +#define SLEEP2 1 /* final sleeping time */ + +```