Hey, I am using the latest graph-tool 2.2.11, and this happens to stop working: Traceback (most recent call last): File "../python/mfptTest.py", line 40, in <module> graph_draw(G, layout="sfdp", output=graphName + ".pdf", eprops = {'arrowsize': 1.0, 'penwidth': Ecap }) File "/Volumes/Data/sebi/.local/lib/python2.6/site-packages/graph_tool/draw/__init__.py", line 274, in graph_draw gvg = gv.graph("G") NameError: global name 'gv' is not defined Inspecting the respective file reveals that gv is indeed not defined... Typo? Regards, -- Sebastian Weber Group of Cell Communication and Control Freiburg Institute for Advanced Studies - FRIAS School of Life Sciences - LIFENET Albert-Ludwigs-Universität Freiburg Albertstr. 19 79104 Freiburg T.: +49-761-203-97237 Fax:+49-761-203-97334