本文实例讲述了python实现矩阵乘法的方法。分享给大家供大家参考。具体实现方法如下：
def matrixmul(a, b):
res = [[0] * len(b[0]) for i in range(len(a))]
for i in range(len(a)):
for j in range(len(b[0])):
for k in range(len(b)):
res[i][j] += a[i][k] * b[k][j]
return res
def matrixmul2(a, b):
return [[sum(a * b for a, b in zip(a, b)) for b in zip(*b)] for a in a]
a = [[1,2], [3,4], [5,6], [7,8]]
b = [[1,2,3,4], [5,6,7,8]]
print matrixmul(a,b)
print matrixmul(b,a)
print “-“*90
print matrixmul2(a,b)
print matrixmul2(b,a)
print “-“*90
from numpy import dot
print map(list,dot(a,b))
print map(list,dot(b,a))
#out:
#[[11, 14, 17, 20], [23, 30, 37, 44], [35, 46, 57, 68], [47, 62, 77, 92]]
#[[50, 60], [114, 140]]
#————————————————————————
#[[11, 14, 17, 20], [23, 30, 37, 44], [35, 46, 57, 68], [47, 62, 77, 92]]
#[[50, 60], [114, 140]]
#————————————————————————
#[[11, 14, 17, 20], [23, 30, 37, 44], [35, 46, 57, 68], [47, 62, 77, 92]]
#[[50, 60], [114, 140]]
希望本文所述对大家的python程序设计有所帮助。