>>> a = np.array([[1,2,3],[2,3,4]]) >>> a array([[1, 2, 3], [2, 3, 4]]) >>> z = np.zeros((2,1), dtype=int64) >>> z array([[0], [0]]) >>> np.append(a, z, axis=1) array([[1, 2, 3, 0], [2, 3, 4, 0]])