An animation of the Rule90 one dimensional Cellular Automaton using Python and Matplotlib.

onedca.py

import matplotlib
matplotlib.use('TKAgg')

import numpy as np
import matplotlib.cm as cm
import matplotlib.pyplot as plt
import matplotlib.animation as animation

N    = 100
ON   = 255
OFF  = 0
vals = (ON, OFF)

def init(n=N, randrow=False):
    grid = np.zeros(shape=(n,n))
    if randrow:
        grid[0] = np.random.choice(vals, n, p=(0.2, 0.8))
    else:
        grid[0,n/2] = ON
    return grid

def update(d):
    global row
    data = grid[row]
    row += 1
    if row >= N: return
    grid[row] = np.array([rule[int(4*data[((j-1))%N]/ON+2*data[j]/ON+data[((j+1))%N]/ON)]
               for j in range(N)])
    mat.set_data(grid)
    return mat


rulenum=90
fig, ax = plt.subplots()
ax.axis('off')
row = 0
grid = init()
rule = [((rulenum/pow(2,i)) % 2) * ON for i in range(8)]
mat = ax.matshow(grid, cmap=cm.Greens)
ani = animation.FuncAnimation(fig, update, frames=99, interval=60, save_count=50, repeat=False)
#ani.save('rule90.mp4', fps=30)
plt.show()