Multiplying numpy arrays
Actually the * operator does element-wise multiplication. So you need to use .dot() function to get the desired result.
Example :
import numpy as np

a = np.array([[1,2,3],
    [4,5,6],
    [7,8,9]])

b =  np.array([[1]
    ,[2],
    [3]])
print(a * b)
print(a.dot(b))

output :
[[ 1  2  3]
 [ 8 10 12]
 [21 24 27]]
[[14]
 [32]
 [50]]

Observe that when I have used * operator, every column in a is multiplied with b element-wise