Colorbar cleanups.

anntzer · anntzer · commit aa387f86710e · 2020-07-04T13:23:53.000+02:00
- Remove unused colorbar private method _extended_N: This method appears
  to never ever have been used ever since it was added to the codebase.
- Shorten a comment about a wishlist item, and delete commented code
  which is clearly similar to the uncommented one just above.
diff --git a/lib/matplotlib/colorbar.py b/lib/matplotlib/colorbar.py
@@ -1007,18 +1007,6 @@ def _central_N(self):
             nb -= 1
         return nb
 
-    def _extended_N(self):
-        """
-        Based on the colormap and extend variable, return the
-        number of boundaries.
-        """
-        N = self.cmap.N + 1
-        if self.extend == 'both':
-            N += 2
-        elif self.extend in ('min', 'max'):
-            N += 1
-        return N
-
     def _get_extension_lengths(self, frac, automin, automax, default=0.05):
         """
         Return the lengths of colorbar extensions.
@@ -1267,13 +1255,7 @@ def add_lines(self, CS, erase=True):
             raise ValueError('add_lines is only for a ContourSet of lines')
         tcolors = [c[0] for c in CS.tcolors]
         tlinewidths = [t[0] for t in CS.tlinewidths]
-        # The following was an attempt to get the colorbar lines
-        # to follow subsequent changes in the contour lines,
-        # but more work is needed: specifically, a careful
-        # look at event sequences, and at how
-        # to make one object track another automatically.
-        #tcolors = [col.get_colors()[0] for col in CS.collections]
-        #tlinewidths = [col.get_linewidth()[0] for lw in CS.collections]
+        # Wishlist: Make colorbar lines auto-follow changes in contour lines.
         ColorbarBase.add_lines(self, CS.levels, tcolors, tlinewidths,
                                erase=erase)
 
