如果是一维数组，可以使用a = a[:,:,-1]实现反转！numpy.flip(m, axis=None)
Reverse the order of elements in an array along the given axis.
The shape of the array is preserved, but the elements are reordered.
把m在axis维度进行切片，并把这个维度的index进行颠倒
示例
随机生成一个二维数组
| 1 2 | import numpy as np a=np.random.randint(1,9,size=9).reshape((3,3)) |
[[5 8 6]
[3 1 7]
[8 7 8]]
axis=0：上下翻转，意味着把行看成整体，行的顺序发生颠倒，每一行的元素不发生改变
| 1 | print(np.flip(a,axis=0)) |
[[8 7 8]
[3 1 7]
[5 8 6]]
axis=1：左右翻转，意味着把列看成整体，列的顺序发生颠倒，每一列的元素不发生改变
| 1 | print(np.flip(a,axis=1)) |
[[6 8 5]
[7 1 3]
[8 7 8]]
