Raise on plural scatter

[MichaelTheFear]

PR summary

Closes #19120

I've created an exception when you pass both singular and plural arguments of pyplot.scatter for edgecolor(s) and linewidth(s), I also created test suits for the exception.

PR checklist

• "closes #0000" is in the body of the PR description to link the related issue
• new and changed code is tested
• [N/A] Plotting related features are demonstrated in an example
• [N/A] New Features and API Changes are noted with a directive and release note
• Documentation complies with general and docstring guidelines

[tacaswell]

Thank you for your work on this, however this logic should live in Axes.scatter not in pyplot. Could you move it there instead?

We already have some logic for resolving these aliases, I am a bit surprised that we did not already handle this case.

[tacaswell]

This should be handled in Axes.scatter not in the pyplot wrapper.

Anyone can clear this review when it is addressed.

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[MichaelTheFear]

Hi @tacaswell I've moved what you asked, and I also moved the tests to the correct test file

[timhoffm]

@MichaelTheFear did you forget to push the tests?

[MichaelTheFear]

Hi! I couldn't understand why some checks were not successful. The fact that they were dependency errors isn't really clear to me. Does anyone know why and how to fix it?

[oscargus]

Not sure these are required as they basically checks that there are no errors in these cases? Or does it complain about not having full coverage if these are not there?

I think the errors now has nothing to do with your PR.

[oscargus]

Sorry that I didn't see this earlier.

[MichaelTheFear]

No problem. Should I remove the asserts?

checks are moved.

[tacaswell]

Both of those look like network issues on the CI side.

We take the alias lw as well which I think will still sneak through.

This is a common enough problem we do have some machinery to automate it (e.g.

matplotlib/lib/matplotlib/artist.py

Lines 1222 to 1226 in e7fd79f

	def set(self, **kwargs):
	# docstring and signature are auto-generated via
	# Artist._update_set_signature_and_docstring() at the end of the
	# module.
	return self._internal_update(cbook.normalize_kwargs(kwargs, self))

) however it seems that we do not use any of that machinery in scatter.

Rather than hard-coding the confilcts, we should at least pull from

matplotlib/lib/matplotlib/collections.py

Lines 27 to 35 in e7fd79f

	@_api.define_aliases({
	"antialiased": ["antialiaseds", "aa"],
	"edgecolor": ["edgecolors", "ec"],
	"facecolor": ["facecolors", "fc"],
	"linestyle": ["linestyles", "dashes", "ls"],
	"linewidth": ["linewidths", "lw"],
	"offset_transform": ["transOffset"],
	})
	class Collection(artist.Artist, cm.ScalarMappable):

.

I'm not clear if this is going to be a simple change or if starting to pull at this is going to keep unraveling!

[MichaelTheFear]

Thank you. @tacaswell Is there anything else that I could do about this PR?

[QuLogic]

I think we'd want to be using cbook.normalize_kwargs here instead of manually checking and raising; the question is whether it should be applied to just the two options here or everything that a Collection aliases as linked by @tacaswell.

[MichaelTheFear]

Sorry about taking so long to resolve this, I've made those requested changes of using cbook.normalize_kwargs, and using the collections aliases

matplotlib/lib/matplotlib/axes/_axes.py

Lines 4555 to 4562 in 63eae54

	# add edgecolors and linewidths to kwargs so they
	# can be processed by normailze_kwargs
	if edgecolors is not None:
	kwargs.update({'edgecolors': edgecolors})
	if linewidths is not None:
	kwargs.update({'linewidths': linewidths})
	kwargs = cbook.normalize_kwargs(kwargs, mcoll.Collection)

and I also had to assign them back to its original variables right after because it was causing and error mainly with linewidths on the cbook._intenal_update

matplotlib/lib/matplotlib/axes/_axes.py

Lines 4562 to 4566 in 63eae54

	kwargs = cbook.normalize_kwargs(kwargs, mcoll.Collection)
	# re direct linewidth and edgecolor so it can be
	# further processed by the rest of the function
	linewidths = kwargs.pop('linewidth', None)
	edgecolors = kwargs.pop('edgecolor', None)

matplotlib/lib/matplotlib/axes/_axes.py

Line 4688 in 63eae54

collection._internal_update(kwargs)

[tacaswell]

This looks good to me!

Would you be willing / able to squash this to one commit?

[MichaelTheFear]

@tacaswell Done 👍

[timhoffm]

Thanks and congratulations on your first contribution to Matplotlib! We'd be happy to see you again.