1 >>> a = np.array([1, 2, 3, 4]);b = np.array((5, 6, 7, 8));c = np.array([[1, 2, 3, 4],[4, 5, 6, 7], [7, 8, 9, 10]]) 2 >>> b 3 array([5, 6, 7, 8]) 4 >>> c 5 array([[ 1,  2,  3,  4], 6        [ 4,  5,  6,  7], 7        [ 7,  8,  9, 10]]) 8 >>> c.dtype 9 dtype(‘int32‘)10 >>> d = a.reshape((2,2))11 >>> d12 array([[1, 2],13        [3, 4]])14 >>> d = a.reshape((1,2))15 Traceback (most recent call last):16   File "<pyshell#27>", line 1, in <module>17     d = a.reshape((1,2))18 ValueError: total size of new array must be unchanged19 >>> d = a.reshape((1,-1))20 >>> d21 array([[1, 2, 3, 4]])

>>> d = a.reshape((-1,1))
>>> d
array([[1],
[2],
[3],
[4]])