fix test for null variables

jhelie · jhelie · commit c628dc260821 · 2017-06-07T11:35:44.000+01:00
diff --git a/lib/mpl_toolkits/axisartist/clip_path.py b/lib/mpl_toolkits/axisartist/clip_path.py
@@ -10,7 +10,7 @@
 import warnings
 
 def atan2(dy, dx):
-    if dx == 0 and dx == 0:
+    if dx == 0 and dy == 0:
         warnings.warn("dx and dy is 0")
         return 0
     else:
