Conway's Game of Life.py

import re

my_colony = """
 *  **   *   *
* *   * * * **
 *   *   *   *
* *   * * *  *
 *  **   *  ***
"""


def check_borders(colony):
    size = [len(colony), len(colony[0])]
    try:
        crop = [
            min([i for i in range(size[0]) if any(colony[i])]),
            max([i for i in range(size[0]) if any(colony[i])]),
            min([j for j in range(size[1]) if any([c[j] for c in colony])]),
            max([j for j in range(size[1]) if any([c[j] for c in colony])]),
            ]
    except ValueError:
        crop = [0,0,0,0]
    colony = [[colony[i][j] for j in range(crop[2], crop[3]+1)] for i in range(crop[0],crop[1]+1)]
    colony = [[0]*len(colony[0])] + colony + [[0]*len(colony[0])]
    colony = [[0]+c+[0] for c in colony]
    return colony


def from_string(string):
    colony = [s for s in string.split('\n') if s!='']
    colony = [[0 if c == ' ' else 1 for c in g] for g in colony]
    longest_line = len(max(colony, key = len))
    colony = [[g[i] if i<len(g) else 0 for i in range(longest_line)] for g in colony]
    return check_borders(colony)


def from_RLE(RLE):
    # described here:
    # http://www.conwaylife.com/wiki/Run_Length_Encoded
    print(RLE)
    string = re.sub(
        r'(\d+)([ob$])',
        lambda x: int(x.group(0)[:-1])*x.group(0)[-1],
        RLE)
    print(string)
    string = re.sub('b', ' ', string)
    string = re.sub(r'\$', ' \n', string)
    return from_string(string)


def progress(colony):
    neighborings = [
            [-1,-1], [-1,0], [-1,+1],
            [ 0,-1],         [ 0,+1],
            [+1,-1], [+1,0], [+1,+1],
        ]
    size = [len(colony), len(colony[0])]
    new_colony = [i.copy() for i in colony]
    for i in range(size[0]):
        for j in range(size[1]):
            neighbors = 0
            for n in neighborings:
                if all([
                        0 <= i+n[0] < size[0],
                        0 <= j+n[1] < size[1],
                    ]):
                    if colony[i+n[0]][j+n[1]]:
                        neighbors += 1
            if neighbors < 2: new_colony[i][j] = 0
            if neighbors > 3: new_colony[i][j] = 0
            if neighbors == 3: new_colony[i][j] = 1
    return check_borders(new_colony)


def show(colony):
    for g in colony:
        print(''.join([' ' + ('o' if c else '·') for c in g]))


if __name__ == '__main__':
    colony = from_string(my_colony)
    ## colony = from_RLE('4b2o$3b4o2$2b6o$3b4o2$2b2o2b2o$2obo2bob2o$3bo2bo3$4b2o$4b2o')
    alive = True
    phases = set()
    generation = 0
    while alive:
        cells_no = sum([sum(i) for i in colony])
        print('Generation {}, {} cells:'.format(generation, cells_no))
        show(colony)
        colony = progress(colony)
        generation += 1
        fingerprint = hash(repr(colony))
        if fingerprint in phases:
            alive = False
        else:
            phases |= {fingerprint}