Python应用：矩阵的乘法—乘积 & 点乘

• 1. 矩阵乘积
• 2. 矩阵点乘

#引入numpy库
import numpy as np

#输入矩阵
A=np.array([[1,1],[2,2],[1,2]])
B=np.array([[1,2,1],[2,2,2]])
C=np.array([[2,1,2],[1,1,1]])

(1) np.dot()
-保证前者的列数和后者的行数一致

F = np.dot(A,B)
>>>[[3 4 3]
 [6 8 6]
 [5 6 5]]

(2) np.matmul()

F = np.matmul(A,B)
>>>[[3 4 3]
 [6 8 6]
 [5 6 5]]

(3) A.dot(B)

F = A.dot(B)
>>>[[3 4 3]
 [6 8 6]
 [5 6 5]]

**(1) ***
-两个矩阵的维度保证一致

F = B * C
>>>[[2 2 2]
 [2 2 2]]

(2) np.multipy()

F = np.multiply(B,C)
>>>[[2 2 2]
 [2 2 2]]