MCVE Code Sample

We have a very verbose warning in 0.15: it prints on every groupby on an object with multidimensional coords.

So the notebook I'm currently working on has red sections like: /home/mroos/.local/lib/python3.7/site-packages/xarray/core/common.py:664: FutureWarning: This DataArray contains multi-dimensional coordinates. In the future, the dimension order of these coordinates will be restored as well unless you specify restore_coord_dims=False. self, group, squeeze=squeeze, restore_coord_dims=restore_coord_dims /home/mroos/.local/lib/python3.7/site-packages/xarray/core/common.py:664: FutureWarning: This DataArray contains multi-dimensional coordinates. In the future, the dimension order of these coordinates will be restored as well unless you specify restore_coord_dims=False. self, group, squeeze=squeeze, restore_coord_dims=restore_coord_dims /home/mroos/.local/lib/python3.7/site-packages/xarray/core/common.py:664: FutureWarning: This DataArray contains multi-dimensional coordinates. In the future, the dimension order of these coordinates will be restored as well unless you specify restore_coord_dims=False. self, group, squeeze=squeeze, restore_coord_dims=restore_coord_dims /home/mroos/.local/lib/python3.7/site-packages/xarray/core/common.py:664: FutureWarning: This DataArray contains multi-dimensional coordinates. In the future, the dimension order of these coordinates will be restored as well unless you specify restore_coord_dims=False. self, group, squeeze=squeeze, restore_coord_dims=restore_coord_dims /home/mroos/.local/lib/python3.7/site-packages/xarray/core/common.py:664: FutureWarning: This DataArray contains multi-dimensional coordinates. In the future, the dimension order of these coordinates will be restored as well unless you specify restore_coord_dims=False. self, group, squeeze=squeeze, restore_coord_dims=restore_coord_dims

Unless there's a way of reducing its verbosity (e.g. only print once per session?), let's aim to push the change through and remove the warning soon?

```python

Your code here

In [2]: import xarray as xr

In [4]: import numpy as np

In [16]: da = xr.DataArray(np.random.rand(2,3), dims=list('ab'))

In [17]: da = da.assign_coords(foo=(('a','b'),np.random.rand(2,3)))

In [18]: da.groupby('a').mean(...)
[...]/python3.6/site-packages/xarray/core/common.py:664: FutureWarning: This DataArray contains multi-dimensional coordinates. In the future, the dimension order of these coordinates will be restored as well unless you specify restore_coord_dims=False. self, group, squeeze=squeeze, restore_coord_dims=restore_coord_dims Out[18]: <xarray.DataArray (a: 2)> array([0.59216558, 0.58616892]) Dimensions without coordinates: a

```

Output of xr.show_versions()

INSTALLED VERSIONS ------------------ commit: None python: 3.6.8 (default, Aug 7 2019, 17:28:10) [GCC 4.8.5 20150623 (Red Hat 4.8.5-39)] python-bits: 64 OS: Linux OS-release: [...] machine: x86_64 processor: x86_64 byteorder: little LC_ALL: None LANG: en_US.utf8 LOCALE: en_US.UTF-8 libhdf5: 1.10.4 libnetcdf: None xarray: 0.15.0 pandas: 0.25.3 numpy: 1.18.1 scipy: 1.4.1 netCDF4: None pydap: None h5netcdf: None h5py: 2.10.0 Nio: None zarr: None cftime: None nc_time_axis: None PseudoNetCDF: None rasterio: None cfgrib: None iris: None bottleneck: None dask: None distributed: None matplotlib: 3.1.2 cartopy: None seaborn: 0.10.0 numbagg: None setuptools: 45.0.0 pip: 20.0.2 conda: None pytest: 5.3.2 IPython: 7.12.0 sphinx: 2.3.1