numpy 理解一维，二维，三维，四维数组

 

一维

>>> import numpy as np
>>> a = np.arange(12)
>>> a
array([ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11])

　　

二维：

>>> a = np.arange(12)
>>> a.reshape(3,4)
array([[ 0,  1,  2,  3],
       [ 4,  5,  6,  7],
       [ 8,  9, 10, 11]])
>>>

　　

三维：

>>> a = np.arange(12)
>>> a
array([ 0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11])
>>> a.reshape(3,4,1)
array([[[ 0],
        [ 1],
        [ 2],
        [ 3]],

       [[ 4],
        [ 5],
        [ 6],
        [ 7]],

       [[ 8],
        [ 9],
        [10],
        [11]]])

　　

四维：

>>> a = np.arange(12)
>>> a.reshape(3,4,1,1)
array([[[[ 0]],

        [[ 1]],

        [[ 2]],

        [[ 3]]],


       [[[ 4]],

        [[ 5]],

        [[ 6]],

        [[ 7]]],


       [[[ 8]],

        [[ 9]],

        [[10]],

        [[11]]]])