added a reversing section

story645 · jklymak · timhoffm · story645 · commit 54d24df86409 · 2022-09-16T13:05:18.000-04:00
Co-authored-by: Jody Klymak &lt;jklymak@gmail.com&gt;
Co-authored-by: Tim Hoffmann &lt;2836374+timhoffm@users.noreply.github.com&gt;
diff --git a/examples/color/colormap_reference.py b/examples/color/colormap_reference.py
@@ -6,7 +6,7 @@
 Reference for colormaps included with Matplotlib.
 
 A reversed version of each of these colormaps is available by appending
-``_r`` to the name, e.g., ``viridis_r``.
+``_r`` to the name, as shown in :ref:`reverse-cmap`.
 
 See :doc:`/tutorials/colors/colormaps` for an in-depth discussion about
 colormaps, including colorblind-friendliness.
@@ -15,7 +15,6 @@
 import numpy as np
 import matplotlib.pyplot as plt
 
-
 cmaps = [('Perceptually Uniform Sequential', [
             'viridis', 'plasma', 'inferno', 'magma', 'cividis']),
          ('Sequential', [
@@ -40,7 +39,6 @@
             'gist_rainbow', 'rainbow', 'jet', 'turbo', 'nipy_spectral',
             'gist_ncar'])]
 
-
 gradient = np.linspace(0, 1, 256)
 gradient = np.vstack((gradient, gradient))
 
@@ -67,7 +65,15 @@ def plot_color_gradients(cmap_category, cmap_list):
 for cmap_category, cmap_list in cmaps:
     plot_color_gradients(cmap_category, cmap_list)
 
-plt.show()
+
+###############################################################################
+# .. _reverse-cmap:
+# Reversing a colormap
+# --------------------
+#
+# A colormap can be reversed by appending ``_r`` to the name. For example:
+
+plot_color_gradients("Original and reversed ", ['viridis', 'viridis_r'])
 
 #############################################################################
 #
