issue_comments: 533036570

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https://github.com/pydata/xarray/issues/2227#issuecomment-533036570 https://api.github.com/repos/pydata/xarray/issues/2227 533036570 MDEyOklzc3VlQ29tbWVudDUzMzAzNjU3MA== 6213168 2019-09-19T08:57:44Z 2019-09-19T08:57:44Z MEMBER

Can we short-circuit the special case where the index of the array used for slicing is the same object as the index being sliced, so no alignment is needed?

```python

time_filter.time._variable is ds.time._variable True %timeit xr.align(time_filter, ds.a) 477 ms ± 13.9 ms per loop (mean ± std. dev. of 7 runs, 1 loop each) ``` the time spent on that align call could be zero!

 
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