Merge pull request #11876 from NelleV/better_error_message

jklymak · web-flow · commit 9f74ea72a843 · 2018-08-18T12:56:45.000-07:00
MAINT Better error message for number of colors versus number of data…
diff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py
@@ -6537,7 +6537,10 @@ def hist(self, x, bins=None, range=None, density=None, weights=None,
         else:
             color = mcolors.to_rgba_array(color)
             if len(color) != nx:
-                raise ValueError("color kwarg must have one color per dataset")
+                error_message = (
+                    "color kwarg must have one color per data set. %d data "
+                    "sets and %d colors were provided" % (len(color), nx))
+                raise ValueError(error_message)
 
         # If bins are not specified either explicitly or via range,
         # we need to figure out the range required for all datasets,
