mulmatrix.py

def scale_matrix(m, s):
    return list(list(s * x for x in row) for row in m)

def print_matrix(m):
    print('--' + ' ' * (len(m[0]) * 10) + '--')
    for row in m:
        print('| ', end='')
        for x in row:
            print('{:10.2f}'.format(x), end='')
        print(' |')
    print('--' + ' ' * (len(m[0]) * 10) + '--')

def mul_matrix(a, b):
    return list(list(
        sum(ax * by for ax, by in zip(a[i], (b[k][j] for k in range(len(b)))))
        for j in range(len(a))) for i in range(len(a)))

a = [[1,2,3],[4,5,6],[7,8,10]]
b = scale_matrix([[-2,-4,3],[-2,11,-6],[3,-6,3]], 1/3)

print_matrix(a)
print_matrix(b)
print_matrix(mul_matrix(a, b))

print()

c = list([x] for x in range(6))
d = [list(range(6))]
print_matrix(c)
print_matrix(d)
print_matrix(mul_matrix(c, d))