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";
}
}
