ca.py

#!/usr/bin/python

class CellularAutomaton(object):
    
    def __init__(self, elements, rulecode):
        self.cells = list(elements)
        self.rule = CARule(rulecode)
        self.length = len(elements)
    
    def __str__(self):
        return ''.join(map(lambda x: '#' if x else '.', self.cells))
    
    def next(self):
        nextgen = [self.rule(self.cells[i:i+3]) for i in xrange(self.length-2)]
        self.cells = [self.cells[0]] + nextgen + [self.cells[-1]]
    

class CARule(object):
    
    def __init__(self, wfcode):
        '''
        wolfram code: given as an integer with base 10, not binary.
        '''
        self.rulenum = wfcode
        self.rule = map(lambda n: bool(int(n)), "{0:08b}".format(wfcode))
        self.rule.reverse()
        # self.rule :: [Bool]
    
    def __call__(self, conditions):
        ''' conditions : [Bool, Bool, Bool] '''
        return self.rule[
            sum([int(a) * 2**i for (i,a) in enumerate(conditions)])]
    
    def __str__(self):
        return "Wolfram Code {0}".format(self.rulenum)


def main():
    import os
    import random
    width = int(os.popen('stty size', 'r').read().split()[1])
    halflength = (width-1)//2
    #firstgen = [0]*halflength+[1]+[0]*halflength
    firstgen = [random.choice((True, False)) for i in xrange(width)]
    mycell = CellularAutomaton(firstgen, 90)
    for i in range(300):
        print mycell
        mycell.next()

if __name__ == '__main__':
    main()