matplotlib/matplotlib — pull request #1503 by ivanov (2012-11-15 19:51:46+00:00)
Title: DOC: 'inout' option for tick_params direction

Thanks to Mike Kaufman for reporting it to mpl-devel list.

I would have just pushed this to the branch myself, but as I'm still not totally clear in my head about the dev cycle, I decided to make a PR instead.