Merge pull request matplotlib#19086 from jklymak/fix-add-scale-to-normalize

FIX: add a default scale to Normalize

Author: QuLogic

lib/matplotlib/colors.py

@@ -1096,6 +1096,7 @@ def __init__(self, vmin=None, vmax=None, clip=False):
         self.vmin = _sanitize_extrema(vmin)
         self.vmax = _sanitize_extrema(vmax)
         self.clip = clip
+        self._scale = scale.LinearScale(axis=None)
 
     @staticmethod
     def process_value(value):
@@ -1629,6 +1630,8 @@ def __init__(self, boundaries, ncolors, clip=False, *, extend='neither'):
         self.Ncmap = ncolors
         self.extend = extend
 
+        self._scale = None  # don't use the default scale.
+
         self._n_regions = self.N - 1  # number of colors needed
         self._offset = 0
         if extend in ('min', 'both'):