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 1173980959,I_kwDOAMm_X85F-Ycf,6379,Dataset groupby returning DataArray broken in some cases,20629530,closed,0,,,1,2022-03-18T20:07:37Z,2022-03-20T18:55:26Z,2022-03-20T18:55:26Z,CONTRIBUTOR,,,,"### What happened? Got a TypeError when resampling a dataset along a dimension, mapping a function to each group. The function returns a DataArray. Failed with : `TypeError: _overwrite_indexes() got an unexpected keyword argument 'variables' ` ### What did you expect to happen? This worked before the merging of #5692. A DataArray was returned as expected. ### Minimal Complete Verifiable Example ```Python import xarray as xr ds = xr.tutorial.open_dataset(""air_temperature"") ds.resample(time=""YS"").map(lambda grp: grp.air.mean(""time"")) ``` ### Relevant log output ```Python --------------------------------------------------------------------------- TypeError Traceback (most recent call last) Input In [37], in ----> 1 ds.resample(time=""YS"").map(lambda grp: grp.air.mean(""time"")) File /opt/miniconda3/envs/xclim-pip/lib/python3.9/site-packages/xarray/core/resample.py:300, in DatasetResample.map(self, func, args, shortcut, **kwargs) 298 # ignore shortcut if set (for now) 299 applied = (func(ds, *args, **kwargs) for ds in self._iter_grouped()) --> 300 combined = self._combine(applied) 302 return combined.rename({self._resample_dim: self._dim}) File /opt/miniconda3/envs/xclim-pip/lib/python3.9/site-packages/xarray/core/groupby.py:999, in DatasetGroupByBase._combine(self, applied) 997 index, index_vars = create_default_index_implicit(coord) 998 indexes = {k: index for k in index_vars} --> 999 combined = combined._overwrite_indexes(indexes, variables=index_vars) 1000 combined = self._maybe_restore_empty_groups(combined) 1001 combined = self._maybe_unstack(combined) TypeError: _overwrite_indexes() got an unexpected keyword argument 'variables' ``` ### Anything else we need to know? In the docstring of `DatasetGroupBy.map` it is not made clear that the passed function should return a dataset, but the opposite is also not said. This worked before and I think the issues comes from #5692, which introduced different signatures for `DataArray._overwrite_indexes` (which is called in my case) and `Dataset._overwrite_indexes` (which is expected by the new `_combine`). If the function passed to `Dataset.resample(...).map` should only return `Dataset`s then I believe a more explicit error is needed, as well as some notice in the docs and a breaking change entry in the changelog. If `DataArray`s should be accepted, then we have a regression here. I may have time to help on this. ### Environment
INSTALLED VERSIONS ------------------ commit: None python: 3.9.6 | packaged by conda-forge | (default, Jul 11 2021, 03:39:48) [GCC 9.3.0] python-bits: 64 OS: Linux OS-release: 5.16.13-arch1-1 machine: x86_64 processor: byteorder: little LC_ALL: None LANG: fr_CA.utf8 LOCALE: ('fr_CA', 'UTF-8') libhdf5: 1.12.0 libnetcdf: 4.7.4 xarray: 2022.3.1.dev16+g3ead17ea pandas: 1.4.0 numpy: 1.20.3 scipy: 1.7.1 netCDF4: 1.5.7 pydap: None h5netcdf: 0.11.0 h5py: 3.4.0 Nio: None zarr: 2.10.0 cftime: 1.5.0 nc_time_axis: 1.3.1 PseudoNetCDF: None rasterio: None cfgrib: None iris: None bottleneck: 1.3.2 dask: 2021.08.0 distributed: 2021.08.0 matplotlib: 3.4.3 cartopy: None seaborn: None numbagg: None fsspec: 2021.07.0 cupy: None pint: 0.18 sparse: None setuptools: 57.4.0 pip: 21.2.4 conda: None pytest: 6.2.5 IPython: 8.0.1 sphinx: 4.1.2
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/6379/reactions"", ""total_count"": 2, ""+1"": 1, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 1}",,completed,13221727,issue 1173997225,I_kwDOAMm_X85F-cap,6380,Attributes of concatenation coordinate are dropped,20629530,closed,0,,,1,2022-03-18T20:31:17Z,2022-03-20T18:53:46Z,2022-03-20T18:53:46Z,CONTRIBUTOR,,,,"### What happened? When concatenating two objects with `xr.concat` along a new dimension given through a `DataArray`, the attributes of this given coordinate are lost in the concatenation. ### What did you expect to happen? I expected the concatenation coordinate to be identical to the 1D DataArray I gave to `concat`. ### Minimal Complete Verifiable Example ```Python import xarray as xr ds = xr.tutorial.open_dataset(""air_temperature"") concat_dim = xr.DataArray([1, 2], dims=(""condim"",), attrs={""an_attr"": ""yep""}, name=""condim"") out = xr.concat([ds, ds], concat_dim) out.condim.attrs ``` Before #5692, I get: ``` {'an_attr': 'yep'} ``` with the current master, I get: ``` {} ``` ### Anything else we need to know? I'm not 100% sure, but I think the change is due to `xr.core.concat._calc_concat_dim_coord` being replaced by `xr.core.concat.__calc_concat_dim_index`. The former didn't touch the concatenation coordinate, while the latter casts it as an index, thus dropping the attributes in the process. If the solution is to add a check in `xr.concat`, I may have time to implement something simple. ### Environment
INSTALLED VERSIONS ------------------ commit: None python: 3.9.6 | packaged by conda-forge | (default, Jul 11 2021, 03:39:48) [GCC 9.3.0] python-bits: 64 OS: Linux OS-release: 5.16.13-arch1-1 machine: x86_64 processor: byteorder: little LC_ALL: None LANG: fr_CA.utf8 LOCALE: ('fr_CA', 'UTF-8') libhdf5: 1.12.0 libnetcdf: 4.7.4 xarray: 2022.3.1.dev16+g3ead17ea pandas: 1.4.0 numpy: 1.20.3 scipy: 1.7.1 netCDF4: 1.5.7 pydap: None h5netcdf: 0.11.0 h5py: 3.4.0 Nio: None zarr: 2.10.0 cftime: 1.5.0 nc_time_axis: 1.3.1 PseudoNetCDF: None rasterio: None cfgrib: None iris: None bottleneck: 1.3.2 dask: 2021.08.0 distributed: 2021.08.0 matplotlib: 3.4.3 cartopy: None seaborn: None numbagg: None fsspec: 2021.07.0 cupy: None pint: 0.18 sparse: None setuptools: 57.4.0 pip: 21.2.4 conda: None pytest: 6.2.5 IPython: 8.0.1 sphinx: 4.1.2
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