Elementary cellular automaton

automata.py

import time


def st(a):
  return "".join([str(k).replace("0","-").replace("1","X") for k in a])


def iter(a,r):
  x=zeroes(width)
  ww=width-1
  for i in range(len(a)):
    if i==0:
      if '0'+str(a[0])+str(a[1]) in r:
        x[0]=1
    elif i==ww:
      if str(a[i-1])+str(a[i])+'0' in r:
        x[i]=1
    else:
      if str(a[i-1])+str(a[i])+str(a[i+1]) in r:
        x[i]=1
  return x

rules=[]
def go(a,r):
  rr=buildRules(r)
  global rules
  rules=rr
  for j in range(length):
    print st(a)
    time.sleep(0.1)
    a=iter(a,rr)


def buildRules(intRule):
  rr=[]
  for i in range(8):
    if (intRule & (2**i)) > 0:
      rr.append(ruleset[7-i])
  return rr

def zeroes(width):
  return [0 for i in range(width)]

width=110
length=20

arr=zeroes(width)

arr[width/2]=1


ruleset=['111','110','101','100','011','010','001','000']

rule=41

go(arr,rule)