Boost C++ Application Development Cookbook - Second Edition

How to do it...

Visualization is done in two phases. In the first phase, we make our program output the graph's description in a text format suitable for Graphviz. In the second phase, we import the output from the first step to the visualization tool. The numbered steps in this recipe are all about the first phase.

1. Let's write the std::ostream operator for graph_type as done in the preceding recipe:

#include <boost/graph/graphviz.hpp>std::ostream& operator<<(std::ostream& out, const graph_type& g) {    detail::vertex_writer<graph_type> vw(g);    boost::write_graphviz(out, g, vw);    return out;}

2. The detail::vertex_writer structure, used in the preceding step, must be defined as follows:

#include <iosfwd>namespace detail { template <class GraphT> ...