do not convert None labels to 'None'

segasai · segasai · commit fe63689cf5c8 · 2012-12-19T13:36:13.000Z
diff --git a/lib/matplotlib/artist.py b/lib/matplotlib/artist.py
@@ -686,7 +686,10 @@ def set_label(self, s):
 
         ACCEPTS: string or anything printable with '%s' conversion.
         """
-        self._label = '%s' % (s, )
+        if s is not None:
+            self._label = '%s' % (s, )
+        else:
+            self._label = None
         self.pchanged()
 
     def get_zorder(self):
