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/2889#issuecomment-482162700,https://api.github.com/repos/pydata/xarray/issues/2889,482162700,MDEyOklzc3VlQ29tbWVudDQ4MjE2MjcwMA==,6815844,2019-04-11T15:28:58Z,2022-01-05T21:59:48Z,MEMBER,"Thanks @mathause 
I also think the current behavior is not perfect but the best.

> I would expect both to return np.nan

I expect that `np.nansum(ds)` is equivalent to `np.sum(not nan values)` and thus should be 0, while `np.mean` should be NaN as @dcherian pointed out.

To me, the future `average` function would also return np.nan for all nan slices.","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,432074821
https://github.com/pydata/xarray/issues/2889#issuecomment-482178469,https://api.github.com/repos/pydata/xarray/issues/2889,482178469,MDEyOklzc3VlQ29tbWVudDQ4MjE3ODQ2OQ==,10194086,2019-04-11T16:08:02Z,2019-04-11T16:08:02Z,MEMBER,Thanks for the feedback. I think I see the reasoning behind it now.,"{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,432074821
https://github.com/pydata/xarray/issues/2889#issuecomment-482158883,https://api.github.com/repos/pydata/xarray/issues/2889,482158883,MDEyOklzc3VlQ29tbWVudDQ4MjE1ODg4Mw==,2448579,2019-04-11T15:19:42Z,2019-04-11T15:19:42Z,MEMBER,"This is correct though isn't it?

Mean = nansum(not nan values)/count(not nan values) = 0/0 ","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,432074821