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[Bug]: Setting the edgecolor when using ax.hist raises Invalid RGBA argument in >=3.10 #29985
Closed as duplicate
Description
Bug summary
An error is raised when using the edgecolor argument with ax.hist.
Code for reproduction
import matplotlib.pyplot as plt
import numpy as np
x = np.random.normal(10000)
fig, ax = plt.subplots()
ax.hist(
x,
edgecolor=(0.5, 0, 0.5, 0.8),
facecolor="None",
)Actual outcome
Traceback (most recent call last):
File "/home/nvaytet/code/mpltoolbox/jupyter/example.py", line 7, in <module>
ax.hist(
File "/home/nvaytet/miniforge3/lib/python3.12/site-packages/matplotlib/_api/deprecation.py", line 453, in wrapper
return func(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^
File "/home/nvaytet/miniforge3/lib/python3.12/site-packages/matplotlib/__init__.py", line 1521, in inner
return func(
^^^^^
File "/home/nvaytet/miniforge3/lib/python3.12/site-packages/matplotlib/axes/_axes.py", line 7266, in hist
p._internal_update(kwargs)
File "/home/nvaytet/miniforge3/lib/python3.12/site-packages/matplotlib/artist.py", line 1233, in _internal_update
return self._update_props(
^^^^^^^^^^^^^^^^^^^
File "/home/nvaytet/miniforge3/lib/python3.12/site-packages/matplotlib/artist.py", line 1209, in _update_props
ret.append(func(v))
^^^^^^^
File "/home/nvaytet/miniforge3/lib/python3.12/site-packages/matplotlib/patches.py", line 386, in set_edgecolor
self._set_edgecolor(color)
File "/home/nvaytet/miniforge3/lib/python3.12/site-packages/matplotlib/patches.py", line 372, in _set_edgecolor
self._edgecolor = colors.to_rgba(color, self._alpha)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/nvaytet/miniforge3/lib/python3.12/site-packages/matplotlib/colors.py", line 316, in to_rgba
rgba = _to_rgba_no_colorcycle(c, alpha)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/nvaytet/miniforge3/lib/python3.12/site-packages/matplotlib/colors.py", line 400, in _to_rgba_no_colorcycle
raise ValueError(f"Invalid RGBA argument: {orig_c!r}")
ValueError: Invalid RGBA argument: np.float64(0.5)
Expected outcome
Should not raise.
Additional information
This raises with matplotlib 3.10.0 & 3.10.1.
No error is raised with 3.9.4.
Operating system
Ubuntu 24.04
Matplotlib Version
3.10.*
Matplotlib Backend
No response
Python version
3.12
Jupyter version
No response
Installation
conda
Activity
rcomer commentedon Apr 29, 2025
Thanks for the clear report @nvaytet. This is already fixed ready for v3.10.2 by #29719.