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
528059041,MDU6SXNzdWU1MjgwNTkwNDE=,3569,Drawing only one contour in FacetGrid,6815953,closed,0,,,1,2019-11-25T12:37:02Z,2020-04-11T16:11:52Z,2020-04-11T16:11:52Z,NONE,,,,"#### MCVE Code Sample
```python
import numpy as np
import matplotlib.pyplot as plt
import xarray as xr
x, y = np.meshgrid(np.arange(12), np.arange(12))
z = xr.DataArray(np.sqrt(x**2 + y**2))
z2 = xr.DataArray(np.sqrt(x**2 + y**2)+1)
ds = xr.concat([z,z2], dim = 'time')
ds['time'] = [0,1]
f, ax = plt.subplots()
ds[0].plot.contour(ax = ax, levels=[4], colors=['k'])
f, ax = plt.subplots()
ds[1].plot.contour(ax = ax, levels=[4], colors=['k'])
ds.plot.contour(col = 'time', levels=[4], colors=['k'])
```
#### Output

#### Expected Output

#### Problem Description
While drawing only one contour was fixed some time ago ([#866](https://github.com/pydata/xarray/issues/866)), single contour plots in FacetGrid do not work for me.
#### Output of ``xr.show_versions()``
INSTALLED VERSIONS
------------------
commit: None
python: 3.6.8 (default, Oct 7 2019, 12:59:55)
[GCC 8.3.0]
python-bits: 64
OS: Linux
OS-release: 4.15.0-65-generic
machine: x86_64
processor: x86_64
byteorder: little
LC_ALL: None
LANG: en_US.UTF-8
LOCALE: en_US.UTF-8
libhdf5: 1.10.2
libnetcdf: 4.6.3
xarray: 0.14.1
pandas: 0.24.2
numpy: 1.17.3
scipy: 1.2.1
netCDF4: 1.5.1.2
pydap: installed
h5netcdf: 0.7.4
h5py: 2.9.0
Nio: None
zarr: 2.3.2
cftime: 1.0.3.4
nc_time_axis: 1.2.0
PseudoNetCDF: None
rasterio: 1.0.5
cfgrib: 0.9.6.2
iris: None
bottleneck: 1.2.1
dask: 2.6.0
distributed: 2.6.0
matplotlib: 3.0.3
cartopy: 0.16.0
seaborn: 0.9.0
numbagg: None
setuptools: 41.0.1
pip: 19.3.1
conda: None
pytest: 4.4.1
IPython: 7.1.1
sphinx: 2.0.1
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/3569/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,completed,13221727,issue
275421319,MDU6SXNzdWUyNzU0MjEzMTk=,1730,404 HTTP Status through PydapDataStore connection to Earth System Grid Federation,6815953,closed,0,,,3,2017-11-20T16:42:30Z,2019-02-04T04:25:01Z,2019-02-04T04:25:01Z,NONE,,,,"#### Code Sample, a copy-pastable example if possible
See my code [here](https://gist.github.com/kuchaale/c90bbea33f587130a1c45517a5e9112b)
#### Problem description
I receive 404 HTTP Status through `PydapDataStore`. The link `dataset_url` is working though.
#### Expected Output
`xarray.Dataset` object
#### Output of ``xr.show_versions()``
INSTALLED VERSIONS
------------------
commit: None
python: 3.5.2.final.0
python-bits: 64
OS: Linux
OS-release: 4.10.0-38-generic
machine: x86_64
processor: x86_64
byteorder: little
LC_ALL: None
LANG: en_US.UTF-8
LOCALE: en_US.UTF-8
xarray: 0.10.0rc2
pandas: 0.20.3
numpy: 1.13.3
scipy: 1.0.0
netCDF4: 1.3.1
h5netcdf: None
Nio: None
bottleneck: 1.2.1
cyordereddict: None
dask: 0.15.4
matplotlib: 2.1.0
cartopy: 0.15.1
seaborn: 0.8.1
setuptools: 36.6.0
pip: 9.0.1
conda: None
pytest: None
IPython: 6.2.1
sphinx: None
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/1730/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,completed,13221727,issue
281020451,MDU6SXNzdWUyODEwMjA0NTE=,1775,AttributeError: 'PydapArrayWrapper' object has no attribute 'shape',6815953,closed,0,,3008859,3,2017-12-11T13:41:20Z,2018-01-09T01:48:13Z,2018-01-09T01:48:13Z,NONE,,,,"#### Code Sample, a copy-pastable example if possible
See my code [here](https://gist.github.com/kuchaale/422a37851113ad0a52b28bc14d296674)
#### Problem description
I received `AttributeError: 'PydapArrayWrapper' object has no attribute 'shape'` when I tried to open `PydapDataStore`. However, everything works when I use `pydap` instead of `xarray`.
#### Expected Output
`xarray.Dataset` object
#### Output of ``xr.show_versions()``
INSTALLED VERSIONS
------------------
commit: None
python: 3.5.2.final.0
python-bits: 64
OS: Linux
OS-release: 4.10.0-38-generic
machine: x86_64
processor: x86_64
byteorder: little
LC_ALL: None
LANG: en_US.UTF-8
LOCALE: en_US.UTF-8
xarray: 0.10.0
pandas: 0.21.0
numpy: 1.13.3
scipy: 1.0.0
netCDF4: 1.3.1
h5netcdf: None
Nio: None
bottleneck: 1.2.1
cyordereddict: None
dask: 0.15.4
matplotlib: 2.1.0
cartopy: 0.15.1
seaborn: 0.8.1
setuptools: 36.6.0
pip: 9.0.1
conda: None
pytest: None
IPython: 6.2.1
sphinx: None
","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/1775/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,completed,13221727,issue
255701612,MDU6SXNzdWUyNTU3MDE2MTI=,1555,TypeError: DataArray.name or Dataset key must be either a string or None for serialization to netCDF files,6815953,closed,0,,,2,2017-09-06T18:34:04Z,2017-09-07T07:38:46Z,2017-09-07T07:38:46Z,NONE,,,,"Consider the following [gist](https://gist.github.com/kuchaale/ffb9534e60f3646d81e501e8202efba2) where I receive the following error: `TypeError: DataArray.name or Dataset key must be either a string or None for serialization to netCDF files`.
I think that I run into a bug when `DataArray.name` is checked by `check_name` function. I think that `k` in the corresponding for loop actually represents `DataArray` not `DataArray.name` itself. Thus, I suggest something like this to fix it:
`for k in dataset:
check_name(k.name)
`","{""url"": ""https://api.github.com/repos/pydata/xarray/issues/1555/reactions"", ""total_count"": 0, ""+1"": 0, ""-1"": 0, ""laugh"": 0, ""hooray"": 0, ""confused"": 0, ""heart"": 0, ""rocket"": 0, ""eyes"": 0}",,completed,13221727,issue