import math
import time
import LFSR
import matplotlib.mlab as mlab
import matplotlib.pyplot as plt
import numpy as np


class Walker:
    def __init__(self, rs):
        self.history=[]
        self.pos = 0
        self.random_source = rs
        
    def step(self):
        if self.random_source.shift()==0:
            step = -1
        else:
            step = 1  
        self.history.append(self.pos)
        self.pos += step
        return self.pos


if __name__ == "__main__":
    num_walkers = 100
    num_steps = 1000
    my_LFSR = LFSR.LFSR(16, int(1000 * time.time()))
    walkers =[Walker(my_LFSR) for i in range(num_walkers)]
    for step in range(num_steps):
        for walker in walkers:
            walker.step()
    three_std_devs = [3*2*math.sqrt(a/2) for a in range(num_steps)]
    plt.bar(range(num_steps), [-a for a in three_std_devs], linewidth = 0, width = 1, color = "y")
    plt.bar(range(num_steps), three_std_devs,linewidth = 0, width=1, color = "y")
    for walker in walkers:
        plt.plot(walker.history)

    plt.show()