I am new to ROS. I am working through the beginner's tutorials. Version: ROS Indigo, OS Kubuntu 14.04. I was trying rosrun turtlesim turtlesim_node and the result was: Segmentation fault ( core dumped). Also I was trying to run rqt and the result was:

Traceback (most recent call last):
File "/opt/ros/indigo/bin/rqt", line 13, in
sys.exit(main.main())
File "/opt/ros/indigo/lib/python2.7/dist-packages/rqtgui/main.py", line 59, in main
return super(Main, self).main(argv, standalone=standalone, pluginargumentprovider=pluginargumentprovider, pluginmanagersettingsprefix=str(hash(os.environ['ROSPACKAGEPATH'])))
File "/opt/ros/indigo/lib/python2.7/dist-packages/qtgui/main.py", line 336, in main
from pythonqtbinding import QTBINDING
File "/opt/ros/indigo/lib/python2.7/dist-packages/pythonqtbinding/init.py", line 55, in
from .bindinghelper import loadUi, QTBINDING, QTBINDINGMODULES, QTBINDINGVERSION # @UnusedImport
File "/opt/ros/indigo/lib/python2.7/dist-packages/pythonqtbinding/bindinghelper.py", line 267, in
getattr(sys, 'SELECTQTBINDINGORDER', None),
File "/opt/ros/indigo/lib/python2.7/dist-packages/pythonqtbinding/bindinghelper.py", line 95, in _selectqtbinding
raise ImportError("Could not find Qt binding (looked for: %s):\n%s" % (', '.join(["'%s'" % b for b in bindingorder]), '\n'.join(errormsgs)))
ImportError: Could not find Qt binding (looked for: 'pyqt', 'pyside'):
ImportError for 'pyqt': /usr/lib/python2.7/dist-packages/PyQt4/QtCore.so: undefined symbol: _ZTI13QStateMachine
ImportError for 'pyside': /usr/lib/x8664-linux-gnu/libpyside-python2.7.so.1.2: undefined symbol: _Z9qBadAllocv

What can I do? Thanks in advance.