On Nov 23, 2004, at 11:23 AM, TC MA wrote:
struct graphStruct { string name; };
Unfortunately, bundled graph properties aren't supported (yet). You can, however, add a graph name
Fixed compile error, but has run time error. Modified graph_property.cpp: int main() { using namespace boost; using std::string; typedef adjacency_list<vecS, vecS, directedS,no_property, property<edge_index_t, int>, property<graph_name_t, string> > graph_t; graph_t g; get_property(g, graph_name) = "graph"; std::cout << "name: " << get_property(g, graph_name) << std::endl; typedef subgraph<graph_t> subgraph_t; subgraph_t sg; get_property(sg, graph_name) = "subgraph"; std::cout << "name: " << get_property(sg, graph_name) << std::endl; return exit_success; } Output: $ bjam ...found 409 targets... ...updating 4 targets... gcc-C++-action /home/tcma/cpp/boosttcma/libs/graph/graph_property.test/gcc/debug/inlining-on/graph_property.o gcc-Link-action /home/tcma/cpp/boosttcma/libs/graph/graph_property Chmod1 /home/tcma/cpp/boosttcma/libs/graph/graph_property execute-test /home/tcma/cpp/boosttcma/libs/graph/graph_property.run ====== BEGIN OUTPUT ====== EXIT STATUS: 139 ====== END OUTPUT ====== /home/tcma/cpp/boosttcma/libs/graph/graph_property > /home/tcma/cpp/boosttcma/libs/graph/graph_property.output 2>&1 status=$? echo >> /home/tcma/cpp/boosttcma/libs/graph/graph_property.output echo EXIT STATUS: $status >> /home/tcma/cpp/boosttcma/libs/graph/graph_property.output if test $status -eq 0 ; then cp -f /home/tcma/cpp/boosttcma/libs/graph/graph_property.output /home/tcma/cpp/boosttcma/libs/graph/graph_property.run fi verbose=1 if test $status -ne 0 ; then verbose=0 fi if test $verbose -eq 0 ; then echo ====== BEGIN OUTPUT ====== cat /home/tcma/cpp/boosttcma/libs/graph/graph_property.output echo ====== END OUTPUT ====== fi exit $status ...failed execute-test /home/tcma/cpp/boosttcma/libs/graph/graph_property.run... ...removing /home/tcma/cpp/boosttcma/libs/graph/graph_property.run ...failed updating 1 target... ...skipped 1 target... ...updated 2 targets... $ cat graph_property.output EXIT STATUS: 139 The expected output should be: $ cat graph_property.output name: graph name: subgraph EXIT STATUS: 0 property using property<graph_name_t, string> (see below).
typedef adjacency_list<vecS, vecS, directedS,no_property, edgeStruct, graphStruct> graph_t;
Change this to:
typedef adjacency_list<vecS, vecS, directedS,
property<graph_name_t, string> > graph_t;
g[e].name = "graphname";
std::cout << "name: " << g[e].name << std::endl;
These two won't compile because we can't get at the graph properties that way. "e" is an edge descriptor, so "g[e]" is going to give you an edgeStruct& back (that's how we were able to set the edge weight ). To get to the graph_name property we just added above, use:
get_property(g, graph_name);
If we can come up with a better syntax for the future, we'll definitely do it. For now, we're stuck with that mess.
typedef subgraph<graph_t> subgraph_t;
You're actually going to run into a minor problem here, because the subgraph adaptor requires an edge_index property that we haven't provided. The easiest way to introduce such a property is to actually mix bundled and non-bundled parameters, like so:
typedef adjacency_list<vecS, vecS, directedS, no_property, property<edge_index_t, int, edgeStruct>, property<graph_name_t, string> > graph_t;
Notice how we put in the edge_index_t property, but ended with an "edgeStruct"? That allows, e.g., g[e].weight to still work, but the subgraph can use
no_property, edgeStruct, the edge index property map directly.
subgraph_t sg; get_property(sg, graph_name) = "subgraph";
std::cout << "name: " << get_property(sg, graph_name) << std::endl;
return exit_success; }
All of this is fine; it's actually what we changed
the above code to.
As you can probably tell, we're still working out
some of the kinks in the bundled properties setup. It's better than what we had before, but we still have a bit of work to do to make it really slick.
Doug
===== TingChong Ma ______________________________________________________________________ Post your free ad now! http://personals.yahoo.ca