在不用numpy.dot()的情况下，python中矩阵AB相乘怎么表示

Question

在不用numpy.dot()的情况下，python中矩阵AB相乘怎么表示，单纯用列表和循环这些。

Answer 1

def multiplyMatrix(A,B):
    #普通矩阵相乘
    row_len = len(A)
    column_len = len(B[0])
    cross_len = len(B)
    res_mat = [[0] * row_len for i in range(column_len)]
    for i in range(row_len):
                for j in range(column_len):
                    for k in range(cross_len):
                        temp = A[i][k] * B[k][j]
                        res_mat[i][j] += temp    
    # print(res_mat)
    return res_mat