# -*- coding: utf-8 -*-
"""
Created on Sun Jan 22 11:04:15 2017

@author: celin
"""

import numpy as np
import matplotlib.pyplot as plt
from matplotlib.animation import FuncAnimation

class UpdateDist(object):
    
    def __init__(self, ax, X, Y):
        self.line, = ax.plot([],[],'k-')
        self.x = [0]
        self.y = [0]
        self.X = X
        self.Y = Y
    #affichage
        Rmax_x = np.max(np.abs(X))
        Rmax_y = np.max(np.abs(Y))
        ax.set_xlim(-Rmax_x, Rmax_x)
        ax.set_ylim(-Rmax_y, Rmax_y)
        ax.set_title('Animation: Recuit simulé, cas simple')

    def ani_init(self):                 
        self.line.set_data([], [])
        return self.line,
    
    def ani(self,i):           #réalisation de l'animation
        self.x += [self.X[i]]
        self.y += [self.Y[i]]
        self.line.set_data(self.x, self.y)
        return self.line

fig, ax = plt.subplots()
N=50
alea_marche1 = (np.random.rand(N) < (1/2))*1  #choix x ou y
alea_marche2 = (np.random.rand(N) < (1/2))*2 - 1 #choix 1 ou -1

pas_x = alea_marche1*alea_marche2
pas_y = (1 - alea_marche1)*alea_marche2

X = np.cumsum(pas_x)
Y = np.cumsum(pas_y)
ud = UpdateDist(ax,X,Y)
anim = FuncAnimation(fig, ud.ani, frames=np.arange(N), init_func=ud.ani_init,
                     interval=20, repeat=False)
plt.show()