Python numpy.squeeze()
numpy.squeeze()函数用于当我们想从一个数组的形状中移除单维条目。
语法 : numpy.squeeze(arr, axis=None )
参数 :
arr :[array_like] 输入阵列。
axis :[无或int或ints的元组,可选] 选择形状中的单维条目的子集。如果选择的轴的形状条目大于1,会产生错误。
返回 :
squeezed[ndarray] 输入的数组,但删除了所有或部分长度为1的维度。这总是一个本身或Arr的一个视图。
代码 #1 :
# Python program explaining
# numpy.squeeze function
import numpy as geek
in_arr = geek.array([[[2, 2, 2], [2, 2, 2]]])
print ("Input array : ", in_arr)
print("Shape of input array : ", in_arr.shape)
out_arr = geek.squeeze(in_arr)
print ("output squeezed array : ", out_arr)
print("Shape of output array : ", out_arr.shape)
输出 :
Input array : [[[2 2 2]
[2 2 2]]]
Shape of input array : (1, 2, 3)
output squeezed array : [[2 2 2]
[2 2 2]]
Shape of output array : (2, 3)
代码 #2 :
# Python program explaining
# numpy.squeeze function
import numpy as geek
in_arr = geek.arange(9).reshape(1, 3, 3)
print ("Input array : ", in_arr)
out_arr = geek.squeeze(in_arr, axis = 0)
print ("output array : ", out_arr)
print("The shapes of Input and Output array : ")
print(in_arr.shape, out_arr.shape)
输出 :
Input array : [[[0 1 2]
[3 4 5]
[6 7 8]]]
output array : [[0 1 2]
[3 4 5]
[6 7 8]]
The shapes of Input and Output array :
(1, 3, 3) (3, 3)
注意 :
**ValueError :**
If axis is not None, and an axis being squeezed is not of length 1.
代码 #3 :
# Python program explaining
# numpy.squeeze function
# when value error occurs
import numpy as geek
in_arr = geek.arange(9).reshape(1, 3, 3)
print ("Input array : ", in_arr)
out_arr = geek.squeeze(in_arr, axis = 1)
print ("output array : ", out_arr)
print("The shapes of Input and Output array : ")
print(in_arr.shape, out_arr.shape)
输出 :
ValueError Traceback (most recent call last)
in ()
5
6 print ("Input array : ", in_arr)
----> 7 out_arr = geek.squeeze(in_arr, axis=1)
8 print ("output array : ", out_arr)
9 print("The shapes of Input and Output array : ")
~\Anaconda3\lib\site-packages\numpy\core\fromnumeric.py in squeeze(a, axis)
1196 try:
1197 # First try to use the new axis= parameter
-> 1198 return squeeze(axis=axis)
1199 except TypeError:
1200 # For backwards compatibility
ValueError: cannot select an axis to squeeze out which has size not equal to one