Permanent calcucator

gistfile1.py

from operator import mul
from math import fsum
from functools import reduce
from itertools import permutations, combinations
 
def prod(lst):
    return reduce(mul, lst, 1)
 
def perm_sq(a):
    n = len(a)
    r = range(n)
    s = permutations(r)
    return fsum(prod(a[i][sigma[i]] for i in r) for sigma in s)

def perm_rect(a):
    n = len(a[0])
    m = len(a)
    res = 0
    for c in combinations(range(n), m):
        temp_matrix = []
        for i in range(m):
            temp_matrix.append([])
            for j in range(m):
                temp_matrix[-1].append(a[i][c[j]])
        res += perm_sq(temp_matrix)
    return res

if __name__ == '__main__':

    a = [[1, 0, 0, 1, 1, 0, 1, 0, 1],
         [1, 1, 0, 0, 1, 1, 0, 0, 1],
         [0, 0, 0, 0, 1, 1, 1, 1, 0],
         [1, 1, 1, 0, 0, 0, 0, 0, 0]]

    print(perm_rect(a))