Is indexing with a variable number of indices supported?

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
30/100
Issue type
Feature
Clarity
Needs clarification
Activity status
Stale
Tech stack
rust
Domain
data

Research direction

Start by reading ArrayBase::slice() and the s! macro, then compare the requested variable-index behavior with the linked NumPy example. A completed investigation should establish whether ndarray supports the operation, identify a documented workaround or define what support would need to add, and update the linked Stack Overflow answer.

Written by the indexing model from the issue text.

Description

I'd like to index a tensor along all but the last axis, getting as a result a 1d view of the innermost axis. I thought I'd be able to use ArrayBase::slice() for this, but I need create the index with the s! macro and I can't figure out how to do that with a variable number of indices (such as if the user provides the coordinates of the spatial dimensions in a tensor, and I want to slice on that leaving a 1d view of the feature dimension where the feature dimension is the innermost dimension).

I asked a stack overflow question for this here, if it is indeed supported then perhaps we could add a stack overflow answer there? If not, when would support be added and is there a workaround in the meantime?

The equivalent numpy feature, which is actually slightly more general than my specific use case since I only need a view on the innermost axis, is here

Dominant language
Rust
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