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
991144834,MDU6SXNzdWU5OTExNDQ4MzQ=,5779,Coordinates have wrong number of elements after a Dataset/DataArray is split by np.split(),25172489,open,0,,,4,2021-09-08T13:32:49Z,2021-09-13T04:34:02Z,,NONE,,,,"<!-- Please include a self-contained copy-pastable example that generates the issue if possible.

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**What happened**:

Tried to split a DataArray containing coordinates using numpy. Surprisingly, coordinates along another dimension than the axis specified to numpy are split. The resulting DataArray is broken since now the number of elements in all coordinates are different from the corresponding dimensions.

**What you expected to happen**:

Coordinates along the correct dimension should be split.

**Minimal Complete Verifiable Example**:

```python
>>> import xarray as xr
>>> import numpy as np
>>> testarr = xr.DataArray(np.zeros((4, 6)), coords={""dim_0"": np.arange(4), ""aux_0"": (""dim_0"", [""a"", ""b"", ""c"", ""d""]), ""aux_1"": (""dim_1"", np.arange(6))})
>>> np.split(testarr, 3, axis=1)
[<xarray.DataArray (dim_0: 4, dim_1: 2)>
/-- array of shape (4, 2), all zero --/
Coordinates:
  * dim_0    (dim_0) int64 0 1
    aux_0    (dim_0) <U1 'a' 'b'
    aux_1    (dim_1) int64 0 1 2 3 4 5
Dimensions without coordinates: dim_1, <xarray.DataArray (dim_0: 4, dim_1: 2)>
/-- array of shape (4, 2), all zero --/
Coordinates:
  * dim_0    (dim_0) int64 2 3
    aux_0    (dim_0) <U1 'c' 'd'
    aux_1    (dim_1) int64 0 1 2 3 4 5
Dimensions without coordinates: dim_1, <xarray.DataArray (dim_0: 4, dim_1: 2)>
/-- array of shape (4, 2), all zero --/
Coordinates:
  * dim_0    (dim_0) int64 
    aux_0    (dim_0) <U1 
    aux_1    (dim_1) int64 0 1 2 3 4 5
Dimensions without coordinates: dim_1]
```

**Anything else we need to know?**:

Yes I know there's probably a better way to achieve what I need using xarray, probably `xarray.apply_ufunc()` or sth. Still, the observed behavior is unexpected.

**Environment**:

<details><summary>Output of <tt>xr.show_versions()</tt></summary>

```python
>>> xr.show_versions()

INSTALLED VERSIONS
------------------
commit: None
python: 3.9.1 (default, Jan 13 2021, 15:21:08) 
[GCC 4.8.5 20150623 (Red Hat 4.8.5-44)]
python-bits: 64
OS: Linux
OS-release: 3.10.0-1160.6.1.el7.x86_64
machine: x86_64
processor: x86_64
byteorder: little
LC_ALL: None
LANG: en_US.UTF-8
LOCALE: ('en_US', 'UTF-8')
libhdf5: 1.12.0
libnetcdf: 4.7.4

xarray: 0.18.2
pandas: 1.2.5
numpy: 1.20.3
scipy: 1.6.3
netCDF4: 1.5.6
pydap: None
h5netcdf: None
h5py: 3.2.1
Nio: None
zarr: None
cftime: 1.5.0
nc_time_axis: None
PseudoNetCDF: None
rasterio: None
cfgrib: None
iris: None
bottleneck: None
dask: 2021.06.0
distributed: None
matplotlib: 3.4.2
cartopy: None
seaborn: None
numbagg: None
pint: None
setuptools: 49.2.1
pip: 21.2.4
conda: None
pytest: 6.2.4
IPython: 7.24.1
sphinx: None
```


</details>
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