Convert math equations to numpy

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This is a memo for coding matrix operations in numpy.

Hadamard product


Matrix multiplication, B)
np.matmul(A, B)
A @ B

Outer product

np.outer(A, B)

Kronecker product

np.kron(A, B)

if a and b are vectors, the Kronecker product is a form of vectorization (or flattening) of the outer product of a and b.

np.kron(a, b) == np.outer(a, b).reshape(-1)

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