Bug summary

Thanks for matplotlib!
tripcolor fails if colors are passed with named argument i.e c=values instead of just values. The error is not very informative and it seems a dangerous practice to ignore kwargs and only use args.

  File "/mnt/session_space/conda_envs/latest39/lib/python3.9/site-packages/matplotlib/tri/tripcolor.py", line 57, in tripcolor
    C = np.asarray(args[0])
IndexError: list index out of range

Code for reproduction

plt.tripcolor(vertices[:,0], vertices[:,1], c=values, triangles=triangles)

Actual outcome

  File "/mnt/session_space/conda_envs/latest39/lib/python3.9/site-packages/matplotlib/tri/tripcolor.py", line 57, in tripcolor
    C = np.asarray(args[0])
IndexError: list index out of range

Expected outcome

a successful plot.

Additional information

No response

Operating system

No response

Matplotlib Version

3.5.1

Matplotlib Backend

No response

Python version

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Jupyter version

No response

Installation

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