在 Python 中反转二维数组中的数组

Question

I have a question wether it is possible to reverse certain arrays in my 2D array.我有一个问题，是否可以反转我的二维数组中的某些数组。 For example例如

a=[[1,2],[3,4],[5,6]] 
a[1:3].reverse()
print(a)

would output:会输出：

[1,2],[5,6],[3,4]

I hope you can help :)我希望你能帮助:)

Answer 1

a = [[1, 2], [3, 4], [5, 6]]
a = a[:1] + list(reversed(a[1:3]))
print(a)

You could also use pure slicing, but imo the previous version is more readable:您也可以使用纯切片，但 imo 以前的版本更具可读性：

a = a[:1] + a[:-3:-1]

Answer 2

Your code is actually reversing a copy, and not changing the underlying array.您的代码实际上是在反转副本，而不是更改底层数组。

I'd do this:我会这样做：

a[1:3] = reversed(a[1:3])

It takes a reversed copy of the elements from 1 to three and puts them into their initial locations.它需要从 1 到 3 的元素的反向副本，并将它们放入它们的初始位置。