pad matrix with zeroes to achieve desired shape in python

Hi I have a 19 x 3 matrix, however I want to make it 513 x 3 matrix.
So i just need to maintain my 19 rows and the remaining zeroes or ones to make up 513
is this possible?

>Solution :

Use append on axis=0:

arr2 = np.zeros((513-19, 3))
new_arr = np.append(arr1, arr2, axis=0)