On Mon, Jun 2, 2008 at 1:28 PM, Imran A. Pirwani <pirwani@cs.uiowa.edu> wrote:
Hi,
I am new to boost. I would like to use the following:
typedef adjacency_list< listS, listS > Graph;
Using a graph defined as above will allow me to call "remove_vertex". I would also like to use "connected_components()" to get connected components after I have removed a bunch of vertices (by calling "remove_vertex").
The example at: http://www.boost.org/doc/libs/1_35_0/libs/graph/example/connected_components... doesn't work for me because of the difference in adjacency lists used. Any help will be greatly appreciated!
Hi Imran, First, you won't be able to add vertices by referencing integers like the example does, but you can do something like: graph_traits<Graph>::vertex_descriptor v1 = add_vertex(G); graph_traits<Graph>::vertex_descriptor v2 = add_vertex(G); ... add_edge(v1,v2,G); You'll also need to create and populate your own vertex index map. When you use a vecS as the vertex storage selector, a vertex index map is implicitly defined for you (the actual index of each vertex in the vector is used as the vertex index), but with a listS, you'll need to index the vertices manually. See http://www.boost.org/doc/libs/1_35_0/libs/graph/doc/faq.html, #5 for how to do this. Next, you need to pass this vertex index map to the connected components function. If you have the vertex index map in a variable called "index", as in the example from the FAQ, you can do this by calling "connected_components(G, &component[0], vertex_index_map(index))" in place of the connected_components call in the example you linked to. Regards, Aaron