Dear all, could you tell me what I am doing wrong in the following script, trying to filter an edge? Best, F. bug.py: import graph_tool as gt _g = gt.Graph() _g.add_vertex(2) _g.add_edge(0,1) print _g _p = _g.new_edge_property('int') for _e in _g.edges() : _p[_e] = 0 _g.set_edge_filter(_p) print _g [Flavien@localhost Downloads]$ python bug.py <Graph object, directed, with 2 vertices and 1 edge at 0x256b990> Traceback (most recent call last): File "bug.py", line 11, in <module> print _g File "/usr/lib/python2.7/site-packages/graph_tool/__init__.py", line 1272, in __repr__ n = self.num_vertices() File "/usr/lib/python2.7/site-packages/graph_tool/__init__.py", line 2048, in num_vertices return self.__graph.GetNumberOfVertices() RuntimeError: Vertex filter is active but edge filter is not. This is a bug.