pydata/pandas — pull request #4024 by danbirken (2013-06-25 05:06:27+00:00)
Title: BUG: Make secondary_y work properly for bar plots GH3598

As far as I'm aware this seems to work properly, but I'm not sure if this was done the previous way for a reason I don't understand.

Fixes: https://github.com/pydata/pandas/issues/3598