Replaced links to colormap packages with link to third-party packages list in MPL docs (#20196)

Ellert van der Velden · web-flow · commit dcffef76109f · 2021-05-10T09:08:52.000-07:00
* Replaced links to colormaps with link to MPL docs

* Improve link to use full RST.
diff --git a/tutorials/colors/colormaps.py b/tutorials/colors/colormaps.py
@@ -4,8 +4,9 @@
 ********************************
 
 Matplotlib has a number of built-in colormaps accessible via
-`.matplotlib.cm.get_cmap`.  There are also external libraries like
-[palettable]_ and [colorcet]_ that have many extra colormaps.
+`.matplotlib.cm.get_cmap`.  There are also external libraries that
+have many extra colormaps, which can be viewed in the
+`Third-party colormaps`_ section of the Matplotlib documentation.
 Here we briefly discuss how to choose between the many options.  For
 help on creating your own colormaps, see
 :doc:`/tutorials/colors/colormap-manipulation`.
@@ -32,8 +33,9 @@
 perceives changes in the lightness parameter as changes in the data
 much better than, for example, changes in hue. Therefore, colormaps
 which have monotonically increasing lightness through the colormap
-will be better interpreted by the viewer. A wonderful example of
-perceptually uniform colormaps is [colorcet]_.
+will be better interpreted by the viewer. Wonderful examples of
+perceptually uniform colormaps can be found in the
+`Third-party colormaps`_ section as well.
 
 Color can be represented in 3D space in various ways. One way to represent color
 is using CIELAB. In CIELAB, color space is represented by lightness,
@@ -414,7 +416,7 @@ def plot_color_gradients(cmap_category, cmap_list):
 # References
 # ==========
 #
-# .. [colorcet] https://colorcet.pyviz.org
+# .. _Third-party colormaps: https://matplotlib.org/mpl-third-party/#colormaps-and-styles
 # .. [Ware] http://ccom.unh.edu/sites/default/files/publications/Ware_1988_CGA_Color_sequences_univariate_maps.pdf
 # .. [Moreland] http://www.kennethmoreland.com/color-maps/ColorMapsExpanded.pdf
 # .. [list-colormaps] https://gist.github.com/endolith/2719900#id7
@@ -424,5 +426,4 @@ def plot_color_gradients(cmap_category, cmap_list):
 # .. [bw] http://www.tannerhelland.com/3643/grayscale-image-algorithm-vb6/
 # .. [colorblindness] http://www.color-blindness.com/
 # .. [IBM] https://doi.org/10.1109/VISUAL.1995.480803
-# .. [palettable] https://jiffyclub.github.io/palettable/
 # .. [turbo] https://ai.googleblog.com/2019/08/turbo-improved-rainbow-colormap-for.html
