# -*- coding: utf-8 -*-
"""
Created on Tue May 27 21:21:19 2014

@author: rlabbe
"""
from filterpy.kalman import UnscentedKalmanFilter as UKF
from filterpy.kalman import MerweScaledSigmaPoints
import matplotlib.pyplot as plt
from matplotlib.patches import Ellipse,Arrow
import math
import numpy as np
import stats
from stats import plot_covariance_ellipse


def show_fixed_lag_numberline():
    fig = plt.figure()
    ax = fig.add_subplot(111)
    ax.set_xlim(0,10)
    ax.set_ylim(0,10)

    # draw lines
    xmin = 1
    xmax = 9
    y = 5
    height = 1

    plt.hlines(y, xmin, xmax)
    plt.vlines(xmin, y - height / 2., y + height / 2.)
    plt.vlines(4.5, y - height / 2., y + height / 2.)
    plt.vlines(6, y - height / 2., y + height / 2.)
    plt.vlines(xmax, y - height / 2., y + height / 2.)
    plt.vlines(xmax-1, y - height / 2., y + height / 2.)

    # add numbers
    plt.text(xmin, y-1.1, '$x_0$', fontsize=20, horizontalalignment='center')
    plt.text(xmax, y-1.1, '$x_k$', fontsize=20, horizontalalignment='center')
    plt.text(xmax-1, y-1.1, '$x_{k-1}$', fontsize=20, horizontalalignment='center')
    plt.text(4.5, y-1.1, '$x_{k-N+1}$', fontsize=20, horizontalalignment='center')
    plt.text(6, y-1.1, '$x_{k-N+2}$', fontsize=20, horizontalalignment='center')
    plt.text(2.7, y-1.1, '.....', fontsize=20, horizontalalignment='center')
    plt.text(7.2, y-1.1, '.....', fontsize=20, horizontalalignment='center')

    plt.axis('off')
    plt.show()

if __name__ == '__main__':

    #show_2d_transform()
    #show_sigma_selections()

    show_sigma_transform(True)
    #show_four_gps()
    #show_sigma_transform()
    #show_sigma_selections()