Re: [Boost-users] [Graph] kamada_kawai_spring_layout runs forever

Hi Sebi, I think your problem is that all your verticies are at the same location.

From the documentation:

" Prior to invoking this algorithm, it is recommended that the vertices be placed along the vertices of a regular n-sided polygon via circle_layouthttp://www.boost.org/libs/graph/doc/circle_layout.html. " -Chris On 8/16/06, Sebi wrote:

hello,

i'm trying to use the boost graph libarary to layout a small (< 10 nodes), fully connected, undirected graph. the problem is, that the kamada_kawai_spring_layout() function never returns. when i comment out the code to set the weights for my graph it works, but then it is of course not of much use for me.

below is the sourcecode i came up with. as i said, when i comment out the line put(weightMap, e, 1.0); it works (i.e. the program finishes after a short time) and all nodes are at the same location i think the problem could be the way i connect the nodes, which is quite clumsy here. maybe someone has a better idea how to accomplish this.

regards and thanks in advance, sebastian mecklenburg

#include "boost/graph/adjacency_list.hpp" #include "boost/graph/graph_traits.hpp" #include "boost/graph/kamada_kawai_spring_layout.hpp" #include <iostream>

using namespace boost;

enum vertex_position_t { vertex_position }; namespace boost { BOOST_INSTALL_PROPERTY(vertex, position); }

struct pos { double x; double y; };

typedef adjacency_list >, // Edge properties property > WUGraph; typedef graph_traits<WUGraph>::vertex_descriptor vertex_descriptor; typedef graph_traits<WUGraph>::edge_descriptor edge_descriptor;

int main(int argc, char *argv[]) { int numNodes = 5;

WUGraph ug; for(int i = 0; i < numNodes; ++i) { vertex_descriptor u = boost::add_vertex(ug); boost::put(vertex_index, ug, u, i); } graph_traits<WUGraph>::vertex_iterator vi, vi_end; graph_traits<WUGraph>::vertex_iterator vj, vj_end;

boost::property_map::type indexMap = get (vertex_index, ug); boost::property_map::type weightMap = get (edge_weight, ug); for (tie(vi, vi_end) = vertices(ug); vi != vi_end; ++vi) { for (tie(vj, vj_end) = vertices(ug); vj != vj_end; ++vj) { int i1 = get(indexMap, *vi); int i2 = get(indexMap, *vj); if(i1 < i2) { edge_descriptor e = add_edge(*vi, *vj, ug).first; put(weightMap, e, 1.0); } } } boost::kamada_kawai_spring_layout(ug, get(vertex_position, ug), get(edge_weight, ug), side_length(50.0));

boost::property_map::type positionMap = get(vertex_position, ug); for (tie(vi, vi_end) = vertices(ug); vi != vi_end; ++vi) { std::cout << " n" << get(vertex_index, ug, *vi) << "[ pos=\"" << (int)positionMap[*vi].x + 25 << ", " << (int)positionMap [*vi].y + 25 << "\" ];\n"; } } _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users