scatter plot with row or col gets hue wrong

[dschwoerer]

What happened:
The colorbar/hue is only for the last subplot, the colorbar for the other figures is ignored.

What you expected to happen:
hue/colorbar is correct - the total min/max values are calculated and used instead.

Minimal Complete Verifiable Example:

import xarray as xr
import numpy as np

ds=xr.Dataset()
ds["a"]=("x","y"), np.arange(4).reshape(2,2)

ds.plot.scatter("a","a",row="x", hue="a")
import matplotlib.pyplot as plt
plt.show()

Anything else we need to know?:
replacing col for row yields same wrong result

I verified this is in master (5735e16) and 0.16.2

Environment:

Output of xr.show_versions()

INSTALLED VERSIONS

commit: None
python: 3.9.1 (default, Jan 20 2021, 00:00:00)
[GCC 10.2.1 20201125 (Red Hat 10.2.1-9)]
python-bits: 64
OS: Linux
OS-release: 4.12.14-122.57-default
machine: x86_64
processor: x86_64
byteorder: little
LC_ALL: None
LANG: en_US.UTF-8
LOCALE: en_US.UTF-8
libhdf5: 1.10.6
libnetcdf: 4.7.3

xarray: 0.16.2
pandas: 1.0.5
numpy: 1.19.4
scipy: 1.5.2
netCDF4: 1.5.3
pydap: None
h5netcdf: None
h5py: 3.1.0
Nio: None
zarr: None
cftime: 1.1.3
nc_time_axis: 1.2.0
PseudoNetCDF: None
rasterio: None
cfgrib: None
iris: None
bottleneck: 1.2.1
dask: 2021.01.1
distributed: None
matplotlib: 3.3.4
cartopy: None
seaborn: None
numbagg: None
pint: None
setuptools: 49.1.3
pip: 20.2.2
conda: None
pytest: None
IPython: 7.18.1
sphinx: 3.2.1

[keewis]

it seems this has already been fixed as a side-effect of #4407 (not sure what change exactly, though). cc @dcherian.

Could you try with 070d815 / v0.17.0, too? 5735e16 is pretty old.

[dschwoerer]

Thanks, it is indeed fixed in 070d815 👍
Should I close #4978 ?

[keewis]

it would be good to have tests for this (maybe by checking the min / max value of the colorbar) to make sure we don't regress. Would you be up for adding those?