Re: [Boost-users] graph cut compilation error

Subject: Re: [Boost-users] graph cut compilation error
From: Jeremiah Willcock (jewillco_at_[hidden])
Date: 2009-09-09 10:44:02

> Jeremiah,
> 
> Thanks for the response. I am very new to boost, so I am not quite getting the Property Map idea.
> It seems like you can just provide a whole list of template arguments that are of type property<> to the adjacency_list
> object. It the kolmogorov example (http://www.boost.org/doc/libs/1_39_0/libs/graph/doc/kolmogorov_max_flow.html) , it looks
> like the only property that is needed is edge_capacity, so I defined EdgeCapacityProperty (it was actually quite a
> complicated property, depending on edge_reverse as well as edge_residual_capacity).  However, I am still getting "conversion
> from error_property_not_found to EdgeCapacityProperty requested" when I try to call the maxflow function. Is this getting
> closer?
> 
> I guess I am following the property<> stuff, but not the property_map<> idea? Here is the latest attempt:
> 
> #include <iostream>                  // for std::cout
> #include <boost/graph/adjacency_list.hpp>
> #include <boost/graph/kolmogorov_max_flow.hpp>
> 
> using namespace boost;
> 
> typedef adjacency_list_traits<vecS, vecS, bidirectionalS> Traits;
> 
> typedef property<edge_reverse_t, Traits::edge_descriptor> EdgeReverseProperty;
> typedef property<edge_residual_capacity_t, long, EdgeReverseProperty> EdgeResidualCapacityProperty;
> typedef property<edge_capacity_t, double, EdgeResidualCapacityProperty> EdgeCapacityProperty;
> 
> typedef adjacency_list<vecS, vecS, bidirectionalS, EdgeCapacityProperty> Graph; //simple
> 
> int main(int,char*[])
> {
>    // declare a graph object
>     Graph g(2); //a graph with 2 vertices
>
>     //add an edge between node 0 and node 1 with weight (capacity) 2.3
>     EdgeCapacityProperty e = 2.3;
>     add_edge(0, 1, e, g);
>
>     //find min cut
>
>     Traits::vertex_descriptor s, t;
>     //double flow = kolmogorov_max_flow(g, s, t); // a list of sources will be returned in s, and a list of sinks will be
> returned in t
>     EdgeCapacityProperty flow = kolmogorov_max_flow(g, s, t); // a list of sources will be returned in s, and a list of
> sinks will be returned in t
>     std::cout << "Max flow is: " << flow << std::endl;
>
>     return 0;
> }
> 
> 
> Thanks,
> 
> David
> 
> 
> Any clues as to what I've done wrong? Maybe a simple example like this could be put on the kolmogorov documentation page?

The error message you get (the conversion error) should mention an 
argument number and a source location where the call with 
property_not_found is being used.  Could you please look up that source 
location and argument number and see which property map the code is trying 
to use?  You added one more map, but the documentation suggests several 
more that are required.  The error message will probably say at least one 
of the missing ones.

-- Jeremiah Willcock