任意尺寸的块状切片

本文介绍了任意尺寸的块状切片的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我想切片一个numpy数组以获得最后一个维度中的第i个索引.对于3D阵列，应为:

I would like to slice a numpy array to obtain the i-th index in the last dimension. For a 3D array, this would be:

slice = myarray[:,:,i]

但是我正在编写一个函数，可以获取任意维度的数组，因此对于4D数组，我需要myarray[:,:,:,i]，依此类推.有没有一种方法可以为任何数组获取此切片，而无需显式编写数组维?

But I am writing a function where I can take an array of arbitrary dimensions, so for a 4D array I'd need myarray[:,:,:,i], and so on. Is there a way I can obtain this slice for any array without explicitly having to write the array dimensions?

推荐答案

有...或Ellipsis，它们正是这样做的:

There is ... or Ellipsis, which does exactly this:

slice = myarray[..., i]

省略号是python对象，如果您想在方括号表示法之外使用它.

Ellipsis is the python object, if you should want to use it outside the square bracket notation.