Merge pull request matplotlib#28796 from ammar-qazi/style_example

Add example of petroff10 in the style sheets to show how to use the color sequence.

Author: timhoffm

galleries/examples/style_sheets/petroff10.py

@@ -0,0 +1,43 @@
+"""
+=====================
+Petroff10 style sheet
+=====================
+
+This example demonstrates the "petroff10" style, which implements the 10-color
+sequence developed by Matthew A. Petroff [1]_ for accessible data visualization.
+The style balances aesthetics with accessibility considerations, making it
+suitable for various types of plots while ensuring readability and distinction
+between data series.
+
+.. [1] https://arxiv.org/abs/2107.02270
+
+"""
+
+import matplotlib.pyplot as plt
+import numpy as np
+
+
+def colored_lines_example(ax):
+    t = np.linspace(-10, 10, 100)
+    nb_colors = len(plt.rcParams['axes.prop_cycle'])
+    shifts = np.linspace(-5, 5, nb_colors)
+    amplitudes = np.linspace(1, 1.5, nb_colors)
+    for t0, a in zip(shifts, amplitudes):
+        y = a / (1 + np.exp(-(t - t0)))
+        line, = ax.plot(t, y, '-')
+        point_indices = np.linspace(0, len(t) - 1, 20, dtype=int)
+        ax.plot(t[point_indices], y[point_indices], 'o', color=line.get_color())
+    ax.set_xlim(-10, 10)
+
+
+def image_and_patch_example(ax):
+    ax.imshow(np.random.random(size=(20, 20)), interpolation='none')
+    c = plt.Circle((5, 5), radius=5, label='patch')
+    ax.add_patch(c)
+
+plt.style.use('petroff10')
+fig, (ax1, ax2) = plt.subplots(ncols=2, figsize=(12, 5))
+fig.suptitle("'petroff10' style sheet")
+colored_lines_example(ax1)
+image_and_patch_example(ax2)
+plt.show()