html_url,issue_url,id,node_id,user,created_at,updated_at,author_association,body,reactions,performed_via_github_app,issue
https://github.com/pydata/xarray/issues/2028#issuecomment-1146877847,https://api.github.com/repos/pydata/xarray/issues/2028,1146877847,IC_kwDOAMm_X85EW_eX,5347026,2022-06-05T20:24:20Z,2022-06-05T20:24:20Z,NONE,"> I agree this is harder that it should be.
> 
> Here's one way:
> 
> ```python
> In [28]: a.where(a.currency=='EUR', drop=True)
> Out[28]:
> <xarray.DataArray (country: 2)>
> array([20., 30.])
> Coordinates:
>   * country   (country) <U7 'Germany' 'France'
>     currency  (country) <U3 'EUR' 'EUR'
> ```
> 
> I'm not sure whether `.sel` should work for non-`IndexVariables` - thoughts?


@max-sixty , perhaps there is any update on OPs question or maybe you can help to achieve the following? 
I would like `sel based on a non-dim coordinate` to be as fast as `sel based on the dim itself`.
Timings:
```python
# sel based on a non-dim coordinate 
# (using this coordinate directly .sel(product_id=26) would result in error ""'no index found for coordinate product_id"")
%timeit xds.sel(product=xds.product_id==26)
1.54 ms ± 64.2 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)

# sel based on the dim itself
%timeit xds.sel(product='GN91 Glove Medium')
499 µs ± 16.1 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)

%timeit xds.where(xds.product_id==26, drop=True)
4.17 ms ± 39 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
```
Anyways, _xarray_ is brilliant and made my week :)","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,309691307