np.dot () matrix multiplication np.dot (x, y) or x.dot (y)
np.zeros ((2,3), dtype = float) to establish a two rows and three columns of the matrix are all 0's, dtype the type
np.dot () matrix multiplication np.dot (x, y) or x.dot (y)
np.zeros ((2,3), dtype = float) to establish a two rows and three columns of the matrix are all 0's, dtype the type