import numpy as np
a = np.array([[4, 3], [0, 1], [6, 9]])
b = np.array([[5], [2]])
np.dot(a, b)
array([[26], [ 2], [48]])
c = np.array([[1, 180], [1, 176], [1,156], [1, 160]])
d = np.array([[15], [0.32]])
np.dot(c, d)
array([[72.6 ], [71.32], [64.92], [66.2 ]])