[Boost-users] Re: A boost.graph edge problem

Found my problem! It was my ltSubgraph functor. Instead of: return s1.m_source < s2.m_source || (!(s1.m_source < s2.m_source) && s1.m_target < s2.m_target); It needed to be: return s1.m_source < s2.m_source || (!(s2.m_source < s1.m_source) && s1.m_target < s2.m_target); Jeffrey Holle wrote:

I'm using boost 1.31.0 and gcc 3.4.2.

While this problem is more of an application code problem, since I got no help on other lists, I trying this one with hopes of a response.

I need to identify parallel edges from my graph, which is defined as: typedef subgraph, EdgeProperty> > DataGraphT; typedef boost::graph_traits <DataGraphT>::edge_descriptor DataEdge;

In the test case that I'm working on, I know I have parallel edges, actually 4 sets of 3.

I'd like to use this code: DataGraph::handleParallelEdges(void) { typedef multiset Edges; Edges edges; graph_traits<DataGraphT>::edge_iterator ei,ei_end; for (tie(ei,ei_end)=boost::edges(dataGraph_);ei!=ei_end;++ei) edges.insert(*ei); for (Edges::const_iterator iter = edges.begin(); iter != edges.end(); advance(iter,edges.count(*iter))) if (edges.count(*iter)>1) cout << "See duplicate" << endl; }

However, when count never returns. The likely cause of this (I suspect) is the ltSubgraph functor. Its definition is:

struct ltSubgraph : public std::binary_function { bool operator() (const DataEdge& s1, const DataEdge& s2) const { return s1.m_source < s2.m_source || (!(s1.m_source < s2.m_source) && s1.m_target < s2.m_target); } };

I say this because I can see that this functor is being continuously called in this infinite loop.

Note that I use this functor in multiple other cases, but not with an associate container that allows duplicate keys.

Is there a problem with this code?