np.dot?is the?dot product?of two matrices.
|A B| . |E F| |A*E+B*G A*F+B*H|
∥∩场＝
|C D| |G H| |C*E+D*G C*F+D*H|
Whereas?np.multiply?does an?element-wise multiplication?of two matrices.
|A B| ⊙ |E F| |A*E B*F|
=
|C D| ? |G H|? ? ? ? |C*G D*H|
When used with?np.sum, the result being equal is merely a coincidence.
>>> np.dot([[1,2], [3,4]], [[1,2], [2,3]])array([[ 5,? 8],? ? ? [11, 18]])
>>> np.multiply([[1,2], [3,4]], [[1,2], [2,3]])array([[ 1,? 4],? ? ? [ 6, 12]])
>>> np.sum(np.dot([[1,2], [3,4]], [[1,2], [2,3]]))42
>>> np.sum(np.multiply([[1,2], [3,4]], [[1,2], [2,3]]))23
