id,node_id,number,title,user,state,locked,assignee,milestone,comments,created_at,updated_at,closed_at,author_association,active_lock_reason,draft,pull_request,body,reactions,performed_via_github_app,state_reason,repo,type
423632904,MDU6SXNzdWU0MjM2MzI5MDQ=,2834,Dropping values along multidimensions,711050,closed,0,,,2,2019-03-21T09:20:54Z,2019-06-07T07:30:39Z,2019-06-07T07:30:39Z,NONE,,,,"I have a multidimentionnal dataset with variables containing NaN values. 
```python
Dimensions:  (lat: 32, lon: 15, time: 3)
Coordinates:
  * lat      (lat) float64 43.5 43.75 44.0 44.25 44.5 ... 50.5 50.75 51.0 51.25
  * lon      (lon) float64 1.0 1.25 1.5 1.75 2.0 2.25 ... 3.5 3.75 4.0 4.25 4.5
    plev     float64 5e+04
  * time     (time) datetime64[ns] 2019-03-09 2019-03-09 2019-03-09
Data variables:
    t        (time, lat, lon) float32 -16.949982 -17.149994 ... -23.049988
    dd       (time, lat, lon) float32 -17.266861 -16.444958 ... -71.54408


d.t.values

array([[[-16.949982, -17.149994, -17.25    , ...,        nan,
                nan,        nan],
        [-16.949982, -17.049988, -17.25    , ...,        nan,
                nan,        nan],
        [-16.949982, -17.049988, -17.149994, ...,        nan,
                nan,        nan],
        ...,
        [       nan,        nan,        nan, ...,        nan,
                nan,        nan],
        [       nan,        nan,        nan, ...,        nan,
                nan,        nan],
        [       nan,        nan,        nan, ...,        nan,
                nan,        nan]],

       [[       nan,        nan,        nan, ...,        nan,
                nan,        nan],
        [       nan,        nan,        nan, ...,        nan,
                nan,        nan],
        [       nan,        nan,        nan, ...,        nan,
                nan,        nan],
        ...,
        [       nan,        nan,        nan, ...,        nan,
                nan,        nan],
        [       nan,        nan,        nan, ...,        nan,
                nan,        nan],
        [       nan,        nan,        nan, ...,        nan,
                nan,        nan]],
...

```
I want to drop this values but keep the associated coordinates . I know I can use the stack feature to have a multiindex. It's working but the real need is to do this along multiples dimensions in the dataset.

Is there an other way to do this ? 

I read `Dropping along multiple dimensions simultaneously is not yet supported` in the xarray.Dataset.dropna documentation. If i correctly understand it could solve this issue. Do you have a plan to support this ?

Thanks and thanks for the amazing work on this librairy
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/2834/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,completed,13221727,issue