c++ - Boost: how to remove all the out-edges for a vertex -


in boost graph library, remove_edge invalidate edge iterator, correct way remove out-edge of vertex, example, trying remove out-edge of vertex 0. code snippet in below not work properly.

graph g(n); graph_traits <graph>::out_edge_iterator ei, ei_end; (boost::tie(ei, ei_end) = out_edges(0, g); ei != ei_end; ++ei) {    vertex targ = target(*ei, g);    cout << "target vtx = " << targ << endl;     if ( edge(0, targ, g).second != 0 )      remove_edge(0, targ, g); }

you call clear_out_edges on source vertex out-edges (http://www.boost.org/doc/libs/1_58_0/libs/graph/doc/adjacency_list.html)

  • void clear_vertex(vertex_descriptor u, adjacency_list& g)

    removes edges , vertex u. vertex still appears in vertex set of graph.

    the affect on descriptor , iterator stability same of invoking remove_edge() of edges have u source or target. 

  • void clear_out_edges(vertex_descriptor u, adjacency_list& g)

    removes out-edges vertex u. vertex still appears in vertex set of graph.

    the affect on descriptor , iterator stability same of invoking remove_edge() of edges have u source.

    this operation not applicable undirected graphs (use clear_vertex() instead). 

  • void clear_in_edges(vertex_descriptor u, adjacency_list& g)

i have support any mutablegraph, there clear_vertex


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