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/pull/4484#issuecomment-704632636,https://api.github.com/repos/pydata/xarray/issues/4484,704632636,MDEyOklzc3VlQ29tbWVudDcwNDYzMjYzNg==,5635139,2020-10-07T01:05:37Z,2020-10-07T01:05:37Z,MEMBER,"
> The motivating use case was that I wanted to compute the dot-product of two DataSets (=all of their matching variables).

Thanks, that's a good case. 

A couple of thoughts:
- Are there many other cases outside of `xr.dot` which only operate on `DataArray`s? If not, we could update that function to take a `Dataset`
- Along those lines, I wonder whether this becomes an underlying function — functions which currently operate only on `DataArray`s could have `Dataset` inputs run through this.
- NB: In many of the computation functions, the logic runs the other way (we define the `DataArray` function to be the `Dataset` operation on a single-variable `Dataset`); having a more consistent way of doing this could make extending functions between `DataArray`s & `Dataset`s easier.
- Maybe jumping ahead — are there functions where the result of `func(ds1, ds2)` shouldn't be that function mapped over the matching variables?

","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,714228717
https://github.com/pydata/xarray/pull/4484#issuecomment-703962448,https://api.github.com/repos/pydata/xarray/issues/4484,703962448,MDEyOklzc3VlQ29tbWVudDcwMzk2MjQ0OA==,5635139,2020-10-06T00:37:46Z,2020-10-06T00:37:46Z,MEMBER,"Hi @kefirbandi , thanks for the PR!

Could I ask what the common use cases for this would be? If I understand correctly, running `map(x, y, lambda x: x + y)` is equivalent to `x + y`.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,714228717