BUG: Series.plot doesn't allow color=None

[igurin-invn]

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Reproducible Example

>>> pd.Series([1, 2, 3]).plot(color=None)

Traceback (most recent call last):

Cell In[45], line 1
pd.Series([1, 2, 3]).plot(color=None)

File ~\Anaconda3\envs\latest\lib\site-packages\pandas\plotting_core.py:1000 in call
return plot_backend.plot(data, kind=kind, **kwargs)

File ~\Anaconda3\envs\latest\lib\site-packages\pandas\plotting_matplotlib_init_.py:71 in plot
plot_obj.generate()

File ~\Anaconda3\envs\latest\lib\site-packages\pandas\plotting_matplotlib\core.py:452 in generate
self._make_plot()

File ~\Anaconda3\envs\latest\lib\site-packages\pandas\plotting_matplotlib\core.py:1369 in _make_plot
colors = self._get_colors()

File ~\Anaconda3\envs\latest\lib\site-packages\pandas\plotting_matplotlib\core.py:993 in _get_colors
return get_standard_colors(

File ~\Anaconda3\envs\latest\lib\site-packages\pandas\plotting_matplotlib\style.py:75 in get_standard_colors
colors = _derive_colors(

File ~\Anaconda3\envs\latest\lib\site-packages\pandas\plotting_matplotlib\style.py:132 in _derive_colors
return _get_colors_from_color(color)

File ~\Anaconda3\envs\latest\lib\site-packages\pandas\plotting_matplotlib\style.py:181 in _get_colors_from_color
return list(_gen_list_of_colors_from_iterable(color))

File ~\Anaconda3\envs\latest\lib\site-packages\pandas\plotting_matplotlib\style.py:214 in _gen_list_of_colors_from_iterable
raise ValueError(f"Invalid color {x}")

ValueError: Invalid color None

Issue Description

DataFrame.plot has a color argument that allows None. Series.plot also has a color argument, but it does not allow None.

The existence of a color argument is not explicitly documented in either case. One would assume that color falls into this bucket:

**kwargs
Options to pass to matplotlib plotting method.

but that doesn't explain why it behaves differently between classes.

Also asked on Stack Overflow.

Expected Behavior

>>> pd.DataFrame([[1, 2, 3]]).plot(color=None)
<AxesSubplot:> # works

Installed Versions

INSTALLED VERSIONS

commit : 2e218d1
python : 3.10.9.final.0
python-bits : 64
OS : Windows
OS-release : 10
Version : 10.0.19043
machine : AMD64
processor : Intel64 Family 6 Model 142 Stepping 12, GenuineIntel
byteorder : little
LC_ALL : None
LANG : en
LOCALE : English_United States.1252

pandas : 1.5.3
numpy : 1.23.5
pytz : 2022.7
dateutil : 2.8.2
setuptools : 65.6.3
pip : 23.0.1
Cython : None
pytest : None
hypothesis : None
sphinx : 5.0.2
blosc : None
feather : None
xlsxwriter : None
lxml.etree : 4.9.1
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 3.1.2
IPython : 8.10.0
pandas_datareader: None
bs4 : 4.11.1
bottleneck : 1.3.5
brotli :
fastparquet : None
fsspec : None
gcsfs : None
matplotlib : 3.7.0
numba : None
numexpr : 2.8.4
odfpy : None
openpyxl : 3.0.10
pandas_gbq : None
pyarrow : None
pyreadstat : None
pyxlsb : None
s3fs : None
scipy : 1.10.0
snappy : None
sqlalchemy : None
tables : None
tabulate : None
xarray : None
xlrd : None
xlwt : None
zstandard : None
tzdata : None

[dannyi96]

The delta b/w Series vs DataFrame implemention seems to be arise here: ( Post call to _validate_color_args )

DataFrame:

def _validate_color_args(self):
   ...
   ...
   
   self.kwds["color"]` ---> ends up being None

Series:

def _validate_color_args(self):
   ...
   ...
   
   self.kwds["color"]` ---> ends up being [None]

This delta between DataFrame vs Series seems to arise from here

pandas/pandas/plotting/_matplotlib/core.py

Lines 376 to 383 in eaacf83

	def _validate_color_args(self):
	if (
	"color" in self.kwds
	and self.nseries == 1
	and not is_list_like(self.kwds["color"])
	):
	# support series.plot(color='green')
	self.kwds["color"] = [self.kwds["color"]]

[dannyi96]

take

[igurin-invn]

FWIW, I tried a workaround:

pd.Series([1, 2, 3]).plot(color=[None])

Gives the same error.