Bug report

Bug summary

In matplotlib 2.0, when using plt.savefig() as a pdf, the negative sign is removed from the y tick labels.

import matplotlib.pyplot as plt

plt.plot([-1, 2], [-1, 2])
plt.savefig('~/Desktop/test.png')
plt.savefig('~/Desktop/test.pdf')

test.pdf

Matplotlib 2.0.0
Python 3.5.2, Linux Mint 18.1
Installed matplotlib from conda, then most recently did conda update --all to upgrade to 2.0.0

Actually, going back and look it appears that this issue is not specific to Matplotlib 2.0.0, but was occurring before that as well.

Actually #2, this appears to be a seaborn issue as it only occurs after I import seaborn. I'll post an issue there.