matplotlib · tacaswell · Aug 22, 2024 · Mar 3, 2024 · Aug 16, 2024 · Aug 16, 2024
diff --git a/doc/users/next_whats_new/ccs_color_cycle.rst b/doc/users/next_whats_new/ccs_color_cycle.rst
@@ -0,0 +1,19 @@
+New more-accessible color cycle
+-------------------------------
+
+A new color cycle named 'petroff10' was added. This cycle was constructed using a
+combination of algorithmically-enforced accessibility constraints, including
+color-vision-deficiency modeling, and a machine-learning-based aesthetics model
+developed from a crowdsourced color-preference survey. It aims to be both
+generally pleasing aesthetically and colorblind accessible such that it could
+serve as a default in the aim of universal design. For more details
+see `Petroff, M. A.: "Accessible Color Sequences for Data Visualization"
+<https://arxiv.org/abs/2107.02270>`_ and related `SciPy talk`_. A demonstration
+is included in the style sheets reference_. To load this color cycle in place
+of the default::
+
+  import matplotlib.pyplot as plt
+  plt.style.use('petroff10')
+
+.. _reference: https://matplotlib.org/gallery/style_sheets/style_sheets_reference.html
+.. _SciPy talk: https://www.youtube.com/watch?v=Gapv8wR5DYU
diff --git a/lib/matplotlib/_cm.py b/lib/matplotlib/_cm.py
@@ -1366,6 +1366,20 @@ def _gist_yarg(x): return 1 - x
 )
 
 
+_petroff10_data = (
+    (0.24705882352941178, 0.5647058823529412,  0.8549019607843137),    # 3f90da
+    (1.0,                 0.6627450980392157,  0.054901960784313725),  # ffa90e
+    (0.7411764705882353,  0.12156862745098039, 0.00392156862745098),   # bd1f01
+    (0.5803921568627451,  0.6431372549019608,  0.6352941176470588),    # 94a4a2
+    (0.5137254901960784,  0.17647058823529413, 0.7137254901960784),    # 832db6
+    (0.6627450980392157,  0.4196078431372549,  0.34901960784313724),   # a96b59
+    (0.9058823529411765,  0.38823529411764707, 0.0),                   # e76300
+    (0.7254901960784313,  0.6745098039215687,  0.4392156862745098),    # b9ac70
+    (0.44313725490196076, 0.4588235294117647,  0.5058823529411764),    # 717581
+    (0.5725490196078431,  0.8549019607843137,  0.8666666666666667),    # 92dadd
+)
+
+
 datad = {
     'Blues': _Blues_data,
     'BrBG': _BrBG_data,

diff --git a/lib/matplotlib/colors.py b/lib/matplotlib/colors.py
@@ -129,6 +129,7 @@ class ColorSequenceRegistry(Mapping):
         'Set1': _cm._Set1_data,
         'Set2': _cm._Set2_data,
         'Set3': _cm._Set3_data,
+        'petroff10': _cm._petroff10_data,
     }
 
     def __init__(self):

diff --git a/lib/matplotlib/mpl-data/stylelib/petroff10.mplstyle b/lib/matplotlib/mpl-data/stylelib/petroff10.mplstyle
@@ -0,0 +1,5 @@
+# Color cycle survey palette from Petroff (2021):
+# https://arxiv.org/abs/2107.02270
+# https://github.com/mpetroff/accessible-color-cycles
+axes.prop_cycle: cycler('color', ['3f90da', 'ffa90e', 'bd1f01', '94a4a2', '832db6', 'a96b59', 'e76300', 'b9ac70', '717581', '92dadd'])
+patch.facecolor: 3f90da
diff --git a/lib/matplotlib/tests/test_colors.py b/lib/matplotlib/tests/test_colors.py
@@ -1634,7 +1634,7 @@ def test_color_sequences():
     assert plt.color_sequences is matplotlib.color_sequences  # same registry
     assert list(plt.color_sequences) == [
         'tab10', 'tab20', 'tab20b', 'tab20c', 'Pastel1', 'Pastel2', 'Paired',
-        'Accent', 'Dark2', 'Set1', 'Set2', 'Set3']
+        'Accent', 'Dark2', 'Set1', 'Set2', 'Set3', 'petroff10']
     assert len(plt.color_sequences['tab10']) == 10
     assert len(plt.color_sequences['tab20']) == 20