Fix +/- typo

dstansby · dstansby · commit a311b969bb03 · 2016-12-02T13:51:12.000Z
diff --git a/lib/matplotlib/colorbar.py b/lib/matplotlib/colorbar.py
@@ -701,7 +701,7 @@ def _process_values(self, b=None):
                     b[-1] = 1.1 * b[-1]
             else:
                 if self._extend_lower():
-                    b[0] = b[0] + 1
+                    b[0] = b[0] - 1
                 if self._extend_upper():
                     b[-1] = b[-1] + 1
         self._process_values(b)
