Arch Linux

Description:
Since matplotlib-1.4.0, Qt5 is the primary backend [1]. The optional dependencies should be adjusted:
* depend on python-pyqt5 to satisfy the default
* optionaly depend on python-pyqt4

[1]: http://matplotlib.org/1.4.0/users/whats_new.html#backends

Additional info:
* package version(s) 1.4.0
* config and/or log files etc.


Steps to reproduce:

>>> import matplotlib.pyplot
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/python3.4/site-packages/matplotlib/pyplot.py", line 108, in <module>
_backend_mod, new_figure_manager, draw_if_interactive, _show = pylab_setup()
File "/usr/lib/python3.4/site-packages/matplotlib/backends/__init__.py", line 32, in pylab_setup
globals(),locals(),[backend_name],0)
File "/usr/lib/python3.4/site-packages/matplotlib/backends/backend_qt5agg.py", line 18, in <module>
from .backend_qt5 import QtCore
File "/usr/lib/python3.4/site-packages/matplotlib/backends/backend_qt5.py", line 32, in <module>
from .qt_compat import QtCore, QtGui, QtWidgets, _getSaveFileName, __version__
File "/usr/lib/python3.4/site-packages/matplotlib/backends/qt_compat.py", line 93, in <module>
from PyQt5 import QtCore, QtGui, QtWidgets
ImportError: No module named 'PyQt5'