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/3349#issuecomment-566132726,https://api.github.com/repos/pydata/xarray/issues/3349,566132726,MDEyOklzc3VlQ29tbWVudDU2NjEzMjcyNg==,24830983,2019-12-16T16:21:18Z,2019-12-16T16:21:18Z,NONE,"> @maboualidev Is your objective to integrate the GeoCat implementation into xarray or keep it standalone ?

[GeoCAT](https://geocat.ucar.edu) is the python version of [NCL](https://www.ncl.ucar.edu) and we are a team at [NCAR](https://ncar.ucar.edu) working on it. I know that the team decision is to make use of Xarray within GeoCAT as much as possible, though. 

","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,499477363
https://github.com/pydata/xarray/issues/3349#issuecomment-565738511,https://api.github.com/repos/pydata/xarray/issues/3349,565738511,MDEyOklzc3VlQ29tbWVudDU2NTczODUxMQ==,24830983,2019-12-14T17:58:34Z,2019-12-14T18:00:08Z,NONE,"Hi @huard Thanks for the reply.

Regarding:

> There does not seem to be matching polyval implementations for any of those nor support for indexing along a time dimension with a non-standard calendar.

There is a pull request on GeoCAT-comp for [ndpolyval](https://github.com/NCAR/geocat-comp/pull/49). I think `polyval` and `polyfit` go hand-in-hand. If we have `ndpolyfit` there must be a also a `ndpolyval`. 

Regarding:

> I see you're storing the residuals in the DataArray attributes. From my perspective, it would be useful to have those directly as DataArrays. Thoughts ?

I see the point and agree with you. I think it is a good idea to be as similar to `NumPy.polyfit` as possible; even for the style of the output. I will see it through to have that changed in GeoCAT.


attn: @clyne and @khallock","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,499477363
https://github.com/pydata/xarray/issues/3349#issuecomment-565675452,https://api.github.com/repos/pydata/xarray/issues/3349,565675452,MDEyOklzc3VlQ29tbWVudDU2NTY3NTQ1Mg==,24830983,2019-12-14T03:01:44Z,2019-12-14T03:03:14Z,NONE,"[geocat.comp.ndpolyfit](https://geocat-comp.readthedocs.io/en/latest/user_api/generated/geocat.comp.ndpolyfit.html#geocat.comp.ndpolyfit) extends `NumPy.polyfit` for multi-dimensional arrays and has support for Xarray and Dask. It does exactly what is requested here.

regards,

@andersy005 @clyne @matt-long @khallock","{""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,499477363