1. Same as the definition of matrix multiplication in linear algebra: ()
(A, B): for two-dimensional matrices, compute the matrix product in the true sense, as defined for matrix multiplication in linear algebra. For one-dimensional matrices, compute the inner product of the two. See the following Python code:
import numpy as np # 2-D array: 2 x 3 two_dim_matrix_one = ([[1, 2, 3], [4, 5, 6]]) # 2-D array: 3 x 2 two_dim_matrix_two = ([[1, 2], [3, 4], [5, 6]]) two_multi_res = (two_dim_matrix_one, two_dim_matrix_two) print('two_multi_res: %s' %(two_multi_res)) # 1-D array one_dim_vec_one = ([1, 2, 3]) one_dim_vec_two = ([4, 5, 6]) one_result_res = (one_dim_vec_one, one_dim_vec_two) print('one_result_res: %s' %(one_result_res))
The results are as follows:
two_multi_res: [[22 28] [49 64]] one_result_res: 32
2. Multiplication of corresponding elements element-wise product: (), or *
In Python, there are 2 ways to implement multiplication of corresponding elements, one is () and the other is *. See the following Python code:
import numpy as np # 2-D array: 2 x 3 two_dim_matrix_one = ([[1, 2, 3], [4, 5, 6]]) another_two_dim_matrix_one = ([[7, 8, 9], [4, 7, 1]]) # Multiply corresponding elements element-wise product element_wise = two_dim_matrix_one * another_two_dim_matrix_one print('element wise product: %s' %(element_wise)) # Multiply corresponding elements element-wise product element_wise_2 = (two_dim_matrix_one, another_two_dim_matrix_one) print('element wise product: %s' % (element_wise_2))
The results are as follows:
element wise product: [[ 7 16 27] [16 35 6]] element wise product: [[ 7 16 27] [16 35 6]]
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