CODEWITHSUNDEEP
c++boostgraphgraphviz
Jim
Jim

Reputation: 4669

How to print a boost graph in graphviz with one of the properties displayed?

I see examples of this when using property maps, but not when using structs to handle the vertices and edges (I think this is called 'bundles').

I have vertices and edges defined as such, in an adjacency list graph.

struct Vertex
{
    string name;
    int some_int;
};

struct Edge
{
    double weight;
};

The graph is constructed as follows:

typedef boost::adjacency_list<boost::listS, boost::vecS, boost::directedS, Vertex, Edge> boost_graph;

I want to print my graph of these objects in Graphviz format, so I can view it as an image. However, I don't only want the nodes and edges. I also want the attribute name on vertices and weight on edges to appear in the image. How can I do this?

Upvotes: 9

Views: 11270

Answers (3)

wu1meng2
wu1meng2

Reputation: 537

Using boost::dynamic_properties (See here) and boost::write_graphviz_dp (See here), you can output the graph with properties defined in customized vertex and edge structs. To register the properties into a boost::dynamic_properties object, you must use reserved attributes, such as label, weight, etc.

One caveat is that the BOOST library (I am using 1.82.0) only supports "node_id" as the attribute name of node id, while the current GraphViz standard uses "id" instead.

#include <boost/graph/adjacency_list.hpp>
#include <boost/graph/graphviz.hpp>
#include <fstream>

struct Vertex {
  int some_int;
  std::string name;
};

struct Edge {
  double weight;
};

using DirectedSimpleGraph =
    boost::adjacency_list<boost::listS, boost::vecS, boost::directedS, Vertex,
                          Edge>;
using VertexSpec = boost::graph_traits<DirectedSimpleGraph>::vertex_descriptor;
using EdgeSpec = boost::graph_traits<DirectedSimpleGraph>::edge_descriptor;

int main() {
  DirectedSimpleGraph graph;
  boost::dynamic_properties dp;

  // "node_id", "label", and "weight" are reserved keywords
  // of the GraphViz DOT Format
  dp.property("node_id", boost::get(&Vertex::some_int, graph));
  dp.property("label", boost::get(&Vertex::name, graph));
  dp.property("weight", boost::get(&Edge::weight, graph));

  // Create vertices with id and label
  VertexSpec v0 = boost::add_vertex(Vertex{0, "Zero"}, graph);
  VertexSpec v1 = boost::add_vertex(Vertex{1, "One"}, graph);
  VertexSpec v2 = boost::add_vertex(Vertex{2, "Two"}, graph);
  VertexSpec v3 = boost::add_vertex(Vertex{3, "Three"}, graph);

  // Create edges with weight
  boost::add_edge(v0, v1, Edge{1.0}, graph);
  boost::add_edge(v0, v2, Edge{2.0}, graph);
  boost::add_edge(v2, v3, Edge{3.0}, graph);

  // Write to file
  std::ofstream graph_file_out("./out.gv");
  boost::write_graphviz_dp(graph_file_out, graph, dp);
}

Upvotes: 0

Vikas
Vikas

Reputation: 8948

I just stumbled upon this question. Although it has an accepted answer, I thought I'll add my version too.

You are using bundled property in your graph. The correct way to get property map from your bundled properties is to use boost::get. So you can do something like:

boost::write_graphviz(std::cout, your_graph,
    boost::make_label_writer(boost::get(&Vertex::name, your_graph)),
    boost::make_label_writer(boost::get(&Edge::weight, your_graph)),
    );

Where your_graph is the graph object you have created.

Upvotes: 32

Dan
Dan

Reputation: 1389

I gave bad info the first time. Here is the correct answer. 

#include <boost/graph/graphviz.hpp>

using namespace boost;

// Graph type
typedef adjacency_list<vecS, vecS, directedS, VertexProperties, EdgeProperty> Graph;
Graph g;
std::vector<std::string> NameVec; // for dot file names


// write the dot file
std::ofstream dotfile (strDotFile.c_str ());
write_graphviz (dotfile, g, make_label_writer(&NameVec[0]));

Upvotes: 6

Related Questions