import os, sys import time import multiprocessing as mp import numpy as np import lib import time def perm_ryser(a): ''' the permanent calculated using the ryser formula. much faster than the naive approach ''' n,n2=a.shape z=np.arange(n) irange=xrange(2**n) get_index=lambda i: (i & (1 << z)) != 0 get_term=lambda index: ((-1)**np.sum(index))*np.prod(np.sum(a[index,:], 0)) indeces=map(get_index, irange) terms=map(get_term, indeces) return np.sum(terms)*((-1)**n) dimension=9 real=np.random.uniform(-1, 1, dimension*dimension).reshape((dimension, dimension)) imag=np.random.uniform(-1, 1, dimension*dimension).reshape((dimension, dimension)) submatrix=real+1j*imag #print lib.permanent(submatrix), perm_ryser(submatrix) #sys.exit(0) #t=time.clock() #for i in range(1000): #perm_ryser(submatrix) #t1=time.clock()-t t=time.clock() for i in range(1000): lib.permanent(submatrix) t2=time.clock()-t print t2 #print t1/t2