[Boost-users] BGL: write_graphviz and bundled properties

From: Fred Labrosse (ffl_at_[hidden])
Date: 2006-04-19 09:23:15

All,

First, I'm very new to boost and BGL, so please forgive me if this is trivial.

I've created a graph (adjacency_list) using bundled properties and am now 
trying to write it as a dot file.  I've written my property writer, but when 
I compile, I get several of:

/usr/include/boost/graph/graphviz.hpp: In function `void 
boost::write_graphviz(std::ostream&, const Graph&, VertexPropertiesWriter, 
EdgePropertiesWriter, GraphPropertiesWriter, VertexID) [with Graph = 
boost::adjacency_list<boost::listS, boost::listS, boost::undirectedS, 
map::place, map::link, boost::no_property, boost::listS>, 
VertexPropertiesWriter = map::placeWriter, EdgePropertiesWriter = 
boost::default_writer, GraphPropertiesWriter = boost::default_writer, 
VertexID = 
boost::adj_list_vertex_property_map<boost::adjacency_list<boost::listS, 
boost::listS, boost::undirectedS, map::place, map::link, boost::no_property, 
boost::listS>, boost::detail::error_property_not_found, const 
boost::detail::error_property_not_found&, boost::vertex_index_t>]':
/usr/include/boost/graph/graphviz.hpp:260: instantiated from `void 
boost::write_graphviz(std::ostream&, const Graph&, VertexPropertiesWriter, 
EdgePropertiesWriter, GraphPropertiesWriter) [with Graph = 
boost::adjacency_list<boost::listS, boost::listS, boost::undirectedS, 
map::place, map::link, boost::no_property, boost::listS>, 
VertexPropertiesWriter = map::placeWriter, EdgePropertiesWriter = 
boost::default_writer, GraphPropertiesWriter = boost::default_writer]'
/usr/include/boost/graph/graphviz.hpp:278: instantiated from `void 
boost::write_graphviz(std::ostream&, const Graph&, VertexWriter) [with Graph 
= map::mapType, VertexWriter = map::placeWriter]'
topologicalMap.h:282: instantiated from here
/usr/include/boost/graph/graphviz.hpp:241: error: no match for 'operator<<' in 
'out << boost::get [with PropertyMap = 
boost::adj_list_vertex_property_map<boost::adjacency_list<boost::listS, 
boost::listS, boost::undirectedS, map::place, map::link, boost::no_property, 
boost::listS>, boost::detail::error_property_not_found, const 
boost::detail::error_property_not_found&, boost::vertex_index_t>, Reference = 
const boost::detail::error_property_not_found&, K = void*](((const 
boost::put_get_helper<const boost::detail::error_property_not_found&, 
boost::adj_list_vertex_property_map<boost::adjacency_list<boost::listS, 
boost::listS, boost::undirectedS, map::place, map::link, boost::no_property, 
boost::listS>, boost::detail::error_property_not_found, const 
boost::detail::error_property_not_found&, boost::vertex_index_t> >&)((const 
boost::put_get_helper<const boost::detail::error_property_not_found&, 
boost::adj_list_vertex_property_map<boost::adjacency_list<boost::listS, 
boost::listS, boost::undirectedS, map::place, map::link, boost::no_property, 
boost::listS>, boost::detail::error_property_not_found, const 
boost::detail::error_property_not_found&, boost::vertex_index_t> >*)
((boost::put_get_helper<const boost::detail::error_property_not_found&, 
boost::adj_list_vertex_property_map<boost::adjacency_list<boost::listS, 
boost::listS, boost::undirectedS, map::place, map::link, boost::no_property, 
boost::listS>, boost::detail::error_property_not_found, const 
boost::detail::error_property_not_found&, boost::vertex_index_t> >*)
(&vertex_id)))), ((void* const&)((void* const*)
(+(&i)->std::_List_iterator<_Tp>::operator* [with _Tp = void*]()))))'
/usr/lib/gcc/x86_64-pc-linux-gnu/3.4.5/include/g++-v3/bits/ostream.tcc:63: 
note: candidates are: std::basic_ostream<_CharT, _Traits>& 
std::basic_ostream<_CharT, _Traits>::operator<<(std::basic_ostream<_CharT, 
_Traits>&(*)(std::basic_ostream<_CharT, _Traits>&)) [with _CharT = char, 
_Traits = std::char_traits<char>]

Not being very good at deciphering all that, I'm not sure what is happening.  
I do understand that it's missing an extraction operator but I'm not sure on 
what.  The actual line in graphviz.hpp is:

      out << get(vertex_id, *i);

Two questions:

- Could somebody tell me exactly what that get returns?

- From the dot format, this should be the name of the vertex in the dot file.  
So this seems to relate to the class used as a property.  My second question 
is then:  If this is the case, why then do we need the property writer since 
we apparently also need the operator<< that could do exactly the same thing?  
(And isn't a ' ' (space) missing between the vertex name and whatever the 
property writer writes (or should that be included in it, which is not 
mentioned by the documentation)?  That was 3 questions then ;-)

Thanks in advance for any replies.

Cheers,

Fred