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 :)