YouTube-simulations/global_ljones.c

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/* Global variables and parameters for lennardjones */
/* Basic math */
#define PI 3.141592654
#define DPI 6.283185307
#define PID 1.570796327
/* shape of domain */
#define D_CIRCLES 20 /* several circles */
#define D_CIRCLES_IN_RECT 201 /* several circles in a rectangle */
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#define NMAXCIRCLES 100000 /* total number of circles/polygons (must be at least NCX*NCY for square grid) */
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#define MAXNEIGH 20 /* max number of neighbours kept in memory */
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#define NMAXOBSTACLES 100 /* max number of obstacles */
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#define NMAXSEGMENTS 1000 /* max number of repelling segments */
#define NMAXGROUPS 50 /* max number of groups of segments */
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#define NMAXCOLLISIONS 200000 /* max number of collisions */
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#define C_SQUARE 0 /* square grid of circles */
#define C_HEX 1 /* hexagonal/triangular grid of circles */
#define C_RAND_DISPLACED 2 /* randomly displaced square grid */
#define C_RAND_PERCOL 3 /* random percolation arrangement */
#define C_RAND_POISSON 4 /* random Poisson point process */
#define C_CLOAK 5 /* invisibility cloak */
#define C_CLOAK_A 6 /* first optimized invisibility cloak */
#define C_LASER 7 /* laser fight in a room of mirrors */
#define C_POISSON_DISC 8 /* Poisson disc sampling */
#define C_GOLDEN_MEAN 10 /* pattern based on vertical shifts by golden mean */
#define C_GOLDEN_SPIRAL 11 /* spiral pattern based on golden mean */
#define C_SQUARE_HEX 12 /* alternating between square and hexagonal/triangular */
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#define C_POOL_TABLE 20 /* pool table initial position */
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#define C_ONE 97 /* one single circle, as for Sinai */
#define C_TWO 98 /* two concentric circles of different type */
#define C_NOTHING 99 /* no circle at all, for comparisons */
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/* pattern of additional obstacles */
#define O_CORNERS 0 /* obstacles in the corners (for Boy b.c.) */
#define O_GALTON_BOARD 1 /* Galton board pattern */
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#define O_GENUS_TWO 2 /* obstacles in corners of L-shape domeain (for genus 2 b.c.) */
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#define O_POOL_TABLE 3 /* obstacles around pockets of pool table */
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#define O_HLINE_HOLE_SPOKES 181 /* tips of spokes for S_HLINE_HOLE_SPOKES segment pattern */
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#define O_CIRCLE 4 /* one circle at the origin */
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#define O_FOUR_CIRCLES 5 /* four circles */
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/* pattern of additional repelling segments */
#define S_RECTANGLE 0 /* segments forming a rectangle */
#define S_CUP 1 /* segments forming a cup (for increasing gravity) */
#define S_HOURGLASS 2 /* segments forming an hour glass */
#define S_PENTA 3 /* segments forming a pentagon with 3 angles of 120° and 2 right angles */
#define S_CENTRIFUGE 4 /* segments forming "centrifuge" (polygon with radial segments) */
#define S_POLY_ELLIPSE 5 /* segments forming a polygonal approximation of an ellipse */
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#define S_POOL_TABLE 6 /* pool table with pockets */
#define S_CENTRIFUGE_RND 7 /* segments forming centrifuge with more rounded bins */
#define S_CENTRIFUGE_LEAKY 8 /* segments forming centrifuge with rounded bins and holes */
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#define S_CIRCLE_EXT 9 /* segments forming a repelling cicle */
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#define S_ROCKET_NOZZLE 10 /* segments forming a rocket with bell-shaped nozzle */
#define S_ROCKET_NOZZLE_ROTATED 101 /* rotated version of rocket with bell-shaped nozzle */
#define S_TWO_ROCKETS 102 /* two different rockets, with nozzles specified by NOZZLE_SHAPE and NOZZLE_SHAPE_B */
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#define S_TWO_CIRCLES_EXT 11 /* segments forming two repelling cicle */
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#define S_DAM 12 /* segments forming a dam that can break */
#define S_DAM_WITH_HOLE 13 /* segments forming a dam in which a hole can open */
#define S_DAM_WITH_HOLE_AND_RAMP 14 /* segments forming a dam in which a hole can open */
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#define S_MAZE 15 /* segments forming a maze */
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#define S_MAZE_DIAG 151 /* segments forming a maze with diagonally opposed exits */
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#define S_EXT_RECTANGLE 16 /* particles outside a rectangle */
#define S_DAM_BRICKS 17 /* dam made of several bricks */
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#define S_HLINE_HOLE 18 /* horizontal line with a hole in the bottom */
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#define S_HLINE_HOLE_SPOKES 181 /* horizontal line with a hole in the bottom and extra spokes */
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#define S_EXT_CIRCLE_RECT 19 /* particles outside a circle and a rectangle */
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#define S_BIN_OPENING 20 /* bin containing particles opening at deactivation time */
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#define S_POLYGON_EXT 21 /* exterior of a regular polygon */
#define S_WEDGE_EXT 22 /* exterior of a wedge */
#define S_MIXER 23 /* exterior of a set of fan of rectangles */
#define S_AIRFOIL 24 /* exterior of an air foil */
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/* particle interaction */
#define I_COULOMB 0 /* Coulomb force */
#define I_LENNARD_JONES 1 /* Lennard-Jones force */
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#define I_LJ_DIRECTIONAL 2 /* Lennard-Jones with direction dependence of square symmetry */
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#define I_LJ_PENTA 3 /* Lennard-Jones with pentagonal symmetry */
#define I_GOLDENRATIO 4 /* Lennard-Jones type with equilibria related by golden ratio */
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#define I_LJ_DIPOLE 5 /* Lennard-Jones with a dipolar angle dependence */
#define I_LJ_QUADRUPOLE 6 /* Lennard-Jones with a quadropolar angle dependence */
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#define I_LJ_WATER 7 /* model for water molecule */
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#define I_VICSEK 8 /* Vicsek-type interaction */
#define I_VICSEK_REPULSIVE 9 /* Vicsek-type interaction with harmonic repulsion */
#define I_VICSEK_SPEED 10 /* Vicsek-type interaction with speed adjustment */
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#define I_VICSEK_SHARK 11 /* Vicsek-type interaction with speed adjustment, and one shark */
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/* Boundary conditions */
#define BC_SCREEN 0 /* harmonic boundary conditions outside screen area */
#define BC_RECTANGLE 1 /* harmonic boundary conditions on a resizeable rectangle */
#define BC_CIRCLE 2 /* harmonic boundary conditions outside a moving circle */
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#define BC_PERIODIC 3 /* periodic boundary conditions */
#define BC_PERIODIC_CIRCLE 4 /* periodic boundary conditions and harmonic b.c. outside moving circle */
#define BC_EHRENFEST 5 /* Ehrenfest urn-type configuration */
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#define BC_PERIODIC_FUNNEL 6 /* funnel with periodic boundary conditions */
#define BC_RECTANGLE_LID 7 /* rectangular container with moving lid */
#define BC_PERIODIC_TRIANGLE 8 /* periodic boundary conditions and harmonic b.c. outside moving triangle */
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#define BC_RECTANGLE_WALL 9 /* rectangular container with vertical movable wall */
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#define BC_KLEIN 11 /* Klein bottle (periodic with twisted vertical parts) */
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#define BC_SCREEN_BINS 12 /* harmonic boundary conditions outside screen area plus "bins" (for Galton board) */
#define BC_BOY 13 /* Boy surface/projective plane (periodic with twisted horizontal and vertical parts) */
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#define BC_GENUS_TWO 14 /* surface of genus 2, obtained by identifying opposite sides of an L shape */
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#define BC_ABSORBING 20 /* "no-return" boundary conditions outside BC area */
#define BC_REFLECT_ABS 21 /* reflecting on lower boundary, and "no-return" boundary conditions outside BC area */
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#define BC_REFLECT_ABS_BOTTOM 22 /* absorbing on lower boundary, and reflecting elsewhere */
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/* Regions for partial thermostat couplings */
#define TH_VERTICAL 0 /* only particles at the right of x = PARTIAL_THERMO_SHIFT are coupled */
#define TH_INSEGMENT 1 /* only particles in region defined by segments are coupled */
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#define TH_INBOX 2 /* only particles in a given box are coupled */
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#define TH_LAYER 3 /* only particles above -LAMBDA are coupled */
#define TH_LAYER_TYPE2 4 /* only particles above highest type 2 particle are coupled */
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/* Gravity schedules */
#define G_INCREASE_RELEASE 1 /* slow increase and instant release */
#define G_INCREASE_DECREASE 2 /* slow increase an decrease */
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/* Rocket shapes */
#define RCK_DISC 0 /* disc-shaped rocket */
#define RCK_RECT 1 /* rectangular rocket */
#define RCK_RECT_HAT 2 /* rectangular rocket with a hat */
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#define RCK_RECT_BAR 3 /* rectangular rocket with a hat and a separating bar */
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/* Nozzle shapes */
#define NZ_STRAIGHT 0 /* straight nozzle */
#define NZ_BELL 1 /* bell-shaped nozzle */
#define NZ_GLAS 2 /* glas-shaped nozzle */
#define NZ_CONE 3 /* cone-shaped nozzle */
#define NZ_TRUMPET 4 /* trumpet-shaped nozzle */
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#define NZ_BROAD 5 /* broad straight nozzle */
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#define NZ_DELAVAL 6 /* a type of de Laval nozzle */
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#define NZ_NONE 99 /* no nozzle */
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/* Types of chemical reactions */
#define CHEM_RPS 0 /* rock-paper-scissors reaction */
#define CHEM_AAB 1 /* reaction A + A -> B */
#define CHEM_ABC 2 /* reaction A + B -> C */
#define CHEM_A2BC 3 /* reaction 2A + B -> C */
#define CHEM_CATALYSIS 4 /* reaction 2A + C -> B + C */
#define CHEM_BAA 5 /* reaction B -> A + A (dissociation) */
#define CHEM_AABAA 6 /* reaction A + A <-> B (reversible) */
#define CHEM_POLYMER 7 /* reaction A + B -> C, A + C -> D, etc */
#define CHEM_POLYMER_DISS 8 /* polimerisation with dissociation */
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#define CHEM_POLYMER_STEP 9 /* step growth polimerisation with dissociation */
#define CHEM_AUTOCATALYSIS 10 /* autocatalytic reaction 2A + B -> 2B */
#define CHEM_CATALYTIC_A2D 11 /* catalytic reaction A + B -> C, A + C -> B + D */
#define CHEM_ABCAB 12 /* reaction A + B <-> C (reversible) */
#define CHEM_ABCDABC 13 /* reactions A + B <-> C, A + C <-> D */
#define CHEM_BZ 14 /* simplified Belousov-Zhabotinski reaction with 6 types (Oregonator) */
#define CHEM_BRUSSELATOR 15 /* Brusselator oscillating reaction */
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#define CHEM_ABDACBE 16 /* A + B -> D, A + C -> B + E */
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/* Initial conditions for chemical reactions */
#define IC_UNIFORM 0 /* all particles have type 1 */
#define IC_UNIFORM2 20 /* all particles have type 2 */
#define IC_RANDOM_UNIF 1 /* particle type chosen uniformly at random */
#define IC_RANDOM_TWO 2 /* particle type chosen randomly between 1 and 2, with TYPE_PROPORTION */
#define IC_CIRCLE 3 /* type 1 in a disc */
#define IC_CATALYSIS 4 /* mix of 1 and 2 in left half, only 1 in right half */
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#define IC_LAYERS 5 /* layer of 2 below 1 */
#define IC_BZ 6 /* initial state for BZ reaction */
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#define IC_SIGNX 7 /* type 1 or 2 depending on sign of x */
#define IC_TWOROCKETS 8 /* type 1 or 2 depending on rocket position */
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#define IC_TWOROCKETS_TWOFUELS 9 /* type 1 and 2 or 1 and 3 depending on rocket */
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/* Plot types */
#define P_KINETIC 0 /* colors represent kinetic energy of particles */
#define P_NEIGHBOURS 1 /* colors represent number of neighbours */
#define P_HEALTH 2 /* colors represent health (for SIR model) */
#define P_BONDS 3 /* draw lattice based on neighbours */
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#define P_ANGLE 4 /* colors represent angle/spin of particle */
#define P_TYPE 5 /* colors represent type of particle */
#define P_DIRECTION 6 /* colors represent direction of velocity */
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#define P_ANGULAR_SPEED 7 /* colors represent angular speed */
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#define P_DIRECT_ENERGY 8 /* hue represents direction, luminosity represents energy */
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#define P_DIFF_NEIGHB 9 /* colors represent number of neighbours of different type */
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#define P_THERMOSTAT 10 /* colors show which particles are coupled to the thermostat */
#define P_INITIAL_POS 11 /* colors depend on initial position of particle */
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#define P_NUMBER 12 /* colors depend on particle number */
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#define P_EMEAN 13 /* averaged kinetic energy (with exponential damping) */
#define P_DIRECT_EMEAN 14 /* averaged version of P_DIRECT_ENERGY */
#define P_NOPARTICLE 15 /* particles are not drawn (only the links between them) */
/* Initial position dependence types */
#define IP_X 0 /* color depends on x coordinate of initial position */
#define IP_Y 1 /* color depends on y coordinate of initial position */
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/* Color schemes */
#define C_LUM 0 /* color scheme modifies luminosity (with slow drift of hue) */
#define C_HUE 1 /* color scheme modifies hue */
#define C_PHASE 2 /* color scheme shows phase */
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#define C_ONEDIM 3 /* use preset 1d color scheme (for Turbo, Viridis, Magma, Inferno, Plasma, Twilight) */
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#define C_ONEDIM_LINEAR 4 /* use preset 1d color scheme with linear scale */
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/* Color palettes */
#define COL_JET 0 /* JET color palette */
#define COL_HSLUV 1 /* HSLUV color palette (perceptually uniform) */
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#define COL_GRAY 2 /* grayscale */
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#define COL_TURBO 10 /* TURBO color palette (by Anton Mikhailov) */
#define COL_VIRIDIS 11 /* Viridis color palette */
#define COL_MAGMA 12 /* Magma color palette */
#define COL_INFERNO 13 /* Inferno color palette */
#define COL_PLASMA 14 /* Plasma color palette */
#define COL_CIVIDIS 15 /* Cividis color palette */
#define COL_PARULA 16 /* Parula color palette */
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#define COL_TWILIGHT 17 /* Twilight color palette */
#define COL_TWILIGHT_SHIFTED 18 /* Shifted twilight color palette */
#define COL_TURBO_CYCLIC 101 /* TURBO color palette (by Anton Mikhailov) corrected to be cyclic, beta */
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#define VICSEK_INT ((INTERACTION == I_VICSEK)||(INTERACTION == I_VICSEK_REPULSIVE)||(INTERACTION == I_VICSEK_SPEED)||(INTERACTION == I_VICSEK_SHARK))
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typedef struct
{
double xc, yc, radius; /* center and radius of circle */
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double angle; /* angle of particle's "spin" */
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short int active; /* circle is active */
double energy; /* dissipated energy */
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double emean; /* mean energy */
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double vx; /* x velocity of particle */
double vy; /* y velocity of particle */
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double omega; /* angular velocity of particle */
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double mass_inv; /* inverse of particle mass */
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double inertia_moment_inv; /* inverse of moment of inertia */
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double fx; /* x component of force on particle */
double fy; /* y component of force on particle */
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double torque; /* torque on particle */
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double dirmean; /* time averaged direction */
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int close_to_boundary; /* has value 1 if particle is close to a boundary */
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short int thermostat; /* whether particle is coupled to thermostat */
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int hashcell; /* hash cell in which particle is located */
int neighb; /* number of neighbours within given distance */
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int diff_neighb; /* number of neighbours of different type */
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int hash_nneighb; /* number of neighbours in hashgrid */
int hashneighbour[9*HASHMAX]; /* particle numbers of neighbours in hashgrid */
double deltax[9*HASHMAX]; /* relative position of neighbours */
double deltay[9*HASHMAX]; /* relative position of neighbours */
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short int type; /* type of particle, for mixture simulations */
short int interaction; /* type of interaction */
double eq_dist; /* equilibrium distance */
double spin_range; /* range of spin-spin interaction */
double spin_freq; /* angular frequency of spin-spin interaction */
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double color_hue; /* color hue of particle, for P_INITIAL_POS plot type */
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int color_rgb[3]; /* RGB colors code of particle, for use in ljones_movie.c */
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} t_particle;
typedef struct
{
int number; /* total number of particles in cell */
int particles[HASHMAX]; /* numbers of particles in cell */
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int nneighb; /* number of neighbouring cells */
int neighbour[9]; /* numbers of neighbouring cells */
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} t_hashgrid;
typedef struct
{
double xc, yc, radius; /* center and radius of circle */
short int active; /* circle is active */
double energy; /* dissipated energy */
double vx; /* x velocity of particle */
double vy; /* y velocity of particle */
double mass_inv; /* inverse of particle mass */
double fx; /* x component of force on particle */
double fy; /* y component of force on particle */
int hashx; /* hash grid positions of particles */
int hashy; /* hash grid positions of particles */
int neighb; /* number of neighbours */
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int health; /* 0 = healthy, 1 = infected, 2 = recovered */
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double infected_time; /* time since infected */
int protected; /* 0 = not protected, 1 = protected */
} t_person;
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typedef struct
{
double xc, yc, radius; /* center and radius of circle */
short int active; /* circle is active */
} t_obstacle;
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typedef struct
{
double x1, x2, y1, y2; /* extremities of segment */
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double xc, yc; /* mid-point of segment */
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double nx, ny; /* normal vector */
double c; /* constant term in cartesian eq nx*x + ny*y = c */
double length; /* length of segment */
short int concave; /* corner is concave, to add extra repelling force */
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short int cycle; /* set to 1 if (x2, y2) is equal to (x1, y1) of next segment */
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short int group; /* group to which segment belongs (for several obstacles) */
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double angle1, angle2; /* angles in which concave corners repel */
short int active; /* segment is active */
double x01, x02, y01, y02; /* initial values of extremities, in case of rotation/translation */
double nx0, ny0; /* initial normal vector */
double angle01, angle02; /* initial values of angles in which concave corners repel */
double fx, fy; /* x and y-components of force on segment */
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double torque; /* torque on segment with respect to its center */
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short int inactivate; /* set to 1 for segment to become inactive at time SEGMENT_DEACTIVATION_TIME */
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} t_segment;
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typedef struct
{
double xc, yc; /* center of circle */
} t_tracer;
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typedef struct
{
double xc, yc; /* center of mass of obstacle */
double angle; /* orientation of obstacle */
double vx, vy; /* velocity of center of mass */
double omega; /* angular velocity */
double mass; /* mass of obstacle */
double moment_inertia; /* moment of inertia */
} t_group_segments;
typedef struct
{
double xc, yc; /* coordinates of centers of mass */
double vx, vy; /* velocities */
double omega; /* angular velocity */
} t_group_data;
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typedef struct
{
double x, y; /* location of collision */
int time; /* time since collision */
int color; /* color hue in case of different collisions */
} t_collision;
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typedef struct
{
int nactive; /* number of active particles */
double beta; /* inverse temperature */
double mean_energy; /* mean energy */
double krepel; /* force constant */
double xmincontainer, xmaxcontainer; /* container size */
double fboundary; /* boundary force */
double pressure; /* pressure */
double gravity; /* gravity */
double radius; /* particle radius */
double angle; /* orientation of obstacle */
double omega; /* angular speed of obstacle */
double bdry_fx, bdry_fy; /* components of boundary force */
} t_lj_parameters;
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int ncircles, nobstacles, nsegments, ngroups = 1, counter = 0;
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