Showing ValueError: shapes (1,3) and (1,3) not aligned: 3 (dim 1) != 1 (dim 0)

By converting the matrix to array by using

n12 = np.squeeze(np.asarray(n2))

X12 = np.squeeze(np.asarray(x1))

solved the issue.

The column of the first matrix and the row of the second matrix should be equal and the order should be like this only

column of first matrix = row of second matrix

and do not follow the below step

row of first matrix  = column of second matrix

it will throw an error

Unlike standard arithmetic, which desires matching dimensions, dot products require that the dimensions are one of:

• (X..., A, B) dot (Y..., B, C) -> (X..., Y..., A, C), where ... means "0 or more different values
• (B,) dot (B, C) -> (C,)
• (A, B) dot (B,) -> (A,)
• (B,) dot (B,) -> ()

Your problem is that you are using np.matrix, which is totally unnecessary in your code - the main purpose of np.matrix is to translate a * b into np.dot(a, b). As a general rule, np.matrix is probably not a good choice.