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数组array和矩阵matrix的乘法略有不同，请自行体会

import numpy as npif 1:  # numpy数组乘法    x1 = np.array([1, 2, 3, 4])    x1 = x1.reshape(1, -1)    a1 = np.array([1, 2, 3, 4])    a1 = a1.reshape(1, -1)    a1 = np.transpose(a1)    print('x:\n', x1, '\nshape:', np.shape(x1))    print('a:\n', a1, '\nshape:', np.shape(a1))    value = x1 * a1    print(value)    mulvalue = np.multiply(x1, a1)    print(mulvalue)    dotvalue = np.dot(x1, a1)    print(dotvalue)if 1:    x2 = np.matrix([1, 2, 3, 4])    a2 = np.matrix([1, 2, 3, 4])    a2 = np.transpose(a2)    print('x2:\n', x2, '\nshape:', np.shape(x2))    print('a2:\n', a2, '\nshape:', np.shape(a2))    value = x2 * a2    print(value)    mulvalue = np.multiply(x2, a2)    print(mulvalue)    dotvalue = np.dot(x2, a2)    print(dotvalue)

结果

x: [[1 2 3 4]] shape: (1, 4)a: [[1] [2] [3] [4]] shape: (4, 1)[[ 1  2  3  4] [ 2  4  6  8] [ 3  6  9 12] [ 4  8 12 16]][[ 1  2  3  4] [ 2  4  6  8] [ 3  6  9 12] [ 4  8 12 16]][[30]]x2: [[1 2 3 4]] shape: (1, 4)a2: [[1] [2] [3] [4]] shape: (4, 1)[[30]][[ 1  2  3  4] [ 2  4  6  8] [ 3  6  9 12] [ 4  8 12 16]][[30]]