用於3D數組的numpy.tile

Question

我必須從兩個值（60，80）中獲得3D數組尺寸（4，2，1）

import numpy as np
array([[[ 60.],
        [ 60.]],
   [[ 60.],
    [ 60.]],
   [[ 80.],
    [ 80.]],
   [[ 80.],
    [ 80.]]])

我做如下

a = np.array([[[ 60.]],
       [[ 80.]]])
np.tile(a, (2, 2,1))

並得到

array([[[ 60.],
        [ 60.]],
       [[ 80.],
        [ 80.]],
       [[ 60.],
        [ 60.]],
       [[ 80.],
        [ 80.]]])

如何獲得期望的數組？

Answer 1

您可以結合使用np.tile和np.repeat ：

a = np.array([[[ 60.]],
       [[ 80.]]])
np.repeat(np.tile(a, (1,2,1)), 2, axis=0)

#array([[[ 60.],
#        [ 60.]],

#       [[ 60.],
#        [ 60.]],

#       [[ 80.],
#        [ 80.]],

#       [[ 80.],
#        [ 80.]]])

或者使用np.repeat + reshape ：

np.repeat(a, 4).reshape(4,2,1)
#array([[[ 60.],
#        [ 60.]],

#       [[ 60.],
#        [ 60.]],

#       [[ 80.],
#        [ 80.]],

#       [[ 80.],
#        [ 80.]]])