1>>> a = np.array([[1, 2], [3, 4]])
2>>> b = np.array([[5, 6]])
3>>> np.concatenate((a, b), axis=0)
4array([[1, 2],
5 [3, 4],
6 [5, 6]])
7>>> np.concatenate((a, b.T), axis=1)
8array([[1, 2, 5],
9 [3, 4, 6]])
10>>> np.concatenate((a, b), axis=None)
11array([1, 2, 3, 4, 5, 6])
12