Merge pull request matplotlib#10626 from matplotlib/auto-backport-of-pr-10568

anntzer · web-flow · commit 066629e552b9 · 2018-02-27T22:15:09.000-08:00
Backport PR matplotlib#10568 on branch v2.2.x
diff --git a/lib/matplotlib/backends/backend_qt5.py b/lib/matplotlib/backends/backend_qt5.py
@@ -269,7 +269,8 @@ def _update_figure_dpi(self):
     def _dpi_ratio(self):
         # Not available on Qt4 or some older Qt5.
         try:
-            return self.devicePixelRatio()
+            # self.devicePixelRatio() returns 0 in rare cases
+            return self.devicePixelRatio() or 1
         except AttributeError:
             return 1
 
