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https://issues.apache.org/jira/browse/ARROW-9432?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17159023#comment-17159023
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Uwe Korn commented on ARROW-9432:
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{quote}In R, negative indices means to take everything except those indices. So
maybe these behaviors should be handled in Python/R, translating the requested
indices to the "normal" form that the C++ library expects?{quote}
Uh, how would that work? I thought we have a 1:1 mapping of index in the array
to a resulting row.
{quote}We should not alter the existing Take implementation hot path.
{quote}
I would rather have a second kernel implementation that is called if one
requests the treatment of negative integers in this way. As one can see, I have
opened two of these "behave-different-on-negative-indices" issues and R seems
to have a third implementation. This shows that these kernels are useful but
that there is no consensus on what they should do.
> [C++/Python] Add option to Take kernel to interpret negative indices as
> indexing from the right
> -----------------------------------------------------------------------------------------------
>
> Key: ARROW-9432
> URL: https://issues.apache.org/jira/browse/ARROW-9432
> Project: Apache Arrow
> Issue Type: New Feature
> Components: C++, Python
> Reporter: Uwe Korn
> Priority: Major
> Fix For: 2.0.0
>
>
> Currently negative integers are explicitly forbidding in the {{Take}} kernel.
> It would be nice to have the option to treat negative integers as "indices
> from the right" instead.
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