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https://issues.apache.org/jira/browse/ARROW-10345?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17217337#comment-17217337
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Yibo Cai commented on ARROW-10345:
----------------------------------
Numpy uses a special compare function to treat NaN as largest floating point
number.
https://github.com/numpy/numpy/blob/578f4e7dca4701637284c782d8c74c0d5b688341/numpy/core/src/npysort/npysort_common.h#L123
Maybe it's better to partition NaN to end of array before sorting, just like
how Nulls are handled currently.
> [C++] NaN breaks sorting
> ------------------------
>
> Key: ARROW-10345
> URL: https://issues.apache.org/jira/browse/ARROW-10345
> Project: Apache Arrow
> Issue Type: Bug
> Components: C++
> Affects Versions: 2.0.0
> Reporter: Antoine Pitrou
> Priority: Major
> Fix For: 3.0.0
>
>
> {code:python}
> >>> import numpy as np
> >>> import pyarrow.compute as pc
> >>> pc.sort_indices([3.0, 4.0, 1.0, 2.0, None])
> <pyarrow.lib.UInt64Array object at 0x7f78368a0c90>
> [
> 2,
> 3,
> 0,
> 1,
> 4
> ]
> >>> pc.sort_indices([3.0, 4.0, np.nan, 1.0, 2.0, None])
> <pyarrow.lib.UInt64Array object at 0x7f783684bf30>
> [
> 0,
> 1,
> 2,
> 3,
> 4,
> 5
> ]
> {code}
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