matplotlib/matplotlib — pull request #1000 by dhyams (2012-07-10 12:03:50+00:00)
Title: Fix traceback for vlines, when an empty list or array passed in for x.

Handle the edge case in matplotlib.axes.vlines where an empty list or array is passed in as x. Previously,
the vlines routine would raise an exception when min(x) was called, if x was an empty list.wq