pydata / pydata/xarray

Should sel with slice objects care about underlying coordinate order?

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Description

If I have a xarray DataArray, that has x-coordinates in descending order, and I try to crop the DataArray using
da.sel(x=slice(10,50)), it gives me empty DataArray. If I use
da.sel(x=slice(50,10)), it finds everything it is supposed to find.

I think it would be useful to be able to use this feature without knowing the exact order of the DataArray. Is this intentional?

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Research direction

Start by reproducing the reported behavior with a DataArray whose x-coordinates descend, comparing da.sel(x=slice(10,50)) with the reversed slice. The issue names no source file or test; done means establishing the intended slice semantics and verifying the behavior with regression coverage.

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Assessment

Tech stack
python
Domain
data
Issue type
Feature
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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