Game of Life !

Yet another implementation of the game of life



In [1]:

    
import numpy as np
import matplotlib.pyplot as plt
%matplotlib nbagg
from matplotlib import animation, rc, cm
rc('animation', html='html5')

A class to rule them all...



In [2]:

    
class GoL:
    """
    A game of life class.
    """
    def __init__(self, X0):
        self.X = np.array(X0).astype(np.int64)
        
    def neighbors(self):
        """
        Returns the number of neigbors of each cell.
        """
        X0 = self.X
        N = np.zeros_like(X0) # Neighbors matrix
        N[:-1, :  ]  += X0[1:  , :  ] # Living cells south
        N[:  , :-1]  += X0[ :  ,1:  ] # Living cells east
        N[1: , :  ]  += X0[ :-1, :  ] # Living cells north
        N[:  ,1:  ]  += X0[ :  , :-1] # Living cells west
        N[:-1, :-1]  += X0[1:  ,1:  ] # Living cells south east
        N[1: , :-1]  += X0[ :-1,1:  ] # Living cells north east
        N[1: , 1: ]  += X0[ :-1, :-1] # Living cells north west
        N[:-1, 1: ]  += X0[1:  , :-1] # Living cells south west
        return N
    
    def iterate(self):
        """
        Iterates one time.
        """
        X0 = self.X
        N = self.neighbors()
        X = np.where(N == 2, X0, 0) # If a cell has 2 neighbors, it keeps its current state.
        X += np.where(N == 3, 1, 0 ) # If a cell has 3 neighbors, it gets alive !
        self.X = X

A starting point



In [3]:

    
X0 = (np.random.rand(50, 50) >.7) * 1
X0









    Out[3]:





array([[1, 0, 0, ..., 0, 0, 1],
       [1, 0, 0, ..., 0, 1, 0],
       [0, 1, 1, ..., 0, 0, 0],
       ..., 
       [0, 1, 0, ..., 1, 1, 1],
       [0, 0, 0, ..., 0, 0, 1],
       [0, 0, 1, ..., 1, 1, 1]])



In [4]:

    
def updatefig(*args):
    g.iterate()
    im.set_array(g.X)
    return im,

g = GoL(X0)
fig = plt.figure()
im = plt.imshow(g.X, interpolation = "nearest", cmap = cm.binary, animated=True)
anim = animation.FuncAnimation(fig, updatefig, frames=200, interval=50, blit=True)

plt.show()



In [5]:

    
def updatefig(*args):
    g.iterate()
    im.set_array(g.X)
    return im,

g = GoL(X0)
fig = plt.figure()
im = plt.imshow(g.X, interpolation = "nearest", cmap = cm.binary, animated=True)
#plt.show()
anim = animation.FuncAnimation(fig, updatefig, frames=200, interval=50, blit=True)
plt.close()
anim