Documentation Link

https://matplotlib.org/devdocs/users/explain/colors/colormaps.html
https://matplotlib.org/devdocs/gallery/color/colormap_reference.html

Problem

Previous versions of the pyplot documentation (pre-3.5)included a list of all the available colormaps, with descriptions, and notably included the information thatgist_gray,gist_yarg andbinary are deprecated, and are identical togray orgray_r.

This information was generated from a docstring that was removed inthis pull request, where it wasconcluded that it was unnecessary to keep it because the same information is covered elsewhere. However, as far as I can see, the information about the deprecation / redundancy of these colormaps is nowhere to be found in the modern documentation.

I ran into this issue because I work on scientific software that provides colormaps and uses matplotlib's selection as a reference -- we probably don't want to include colormaps that are just duplicates. I was sure that I saw the information about these three colormapssomewhere, and fell down a rabbithole trying to figure out when and why it was removed and whether it was still accurate.

Suggested improvement

Restore the information about the deprecated colormaps somewhere in the docs, either in thetutorial or in thereference.