fix small error in poly_editor example

Will Silva · Will Silva · commit 23ed8ffd48c3 · 2016-10-26T09:50:08.000-07:00
* if vertex 0 is grabbed, the last point of the poly should be updated as well
diff --git a/examples/event_handling/poly_editor.py b/examples/event_handling/poly_editor.py
@@ -141,6 +141,8 @@ def motion_notify_callback(self, event):
         x, y = event.xdata, event.ydata
 
         self.poly.xy[self._ind] = x, y
+        if self._ind == 0:
+            self.poly.xy[-1] = x, y
         self.line.set_data(zip(*self.poly.xy))
 
         self.canvas.restore_region(self.background)
