Re: [Boost-users] [Graph] I could not get the reversed graph!

On Fri, 2007-07-06 at 13:17 -0500, jiangfan shi wrote:

HI, All,

I could not get a instance of reversed graph by calling make_reverse_graph(g).

That is, I have following type: typedef adjacency_list< listS, listS, bidirectionalS, property, no_property> G;

typedef reverse_graph ReverseG; //Maybe something wrong here.

After I call make_revserse_graph(G) as following, I could not get a instance of modified graph by accessing some fields of ReverseG.

ReverseG tmp=boost::make_reverse_graph(g); //I try to get the reservsed graph here.

The only field is tmp.m_g, which is G& type and the original graph, but is not the reversed graph.

The reverse_graph class template in the BGL is a reversed *view* of the existing graph. It costs essentially nothing to build this view, but when you look at the reverse_graph of a graph you see all of its edges going backwards (the actual storage in the graph is unchanged). Because it's a view, changes to the original graph will show up immediately in the reversed graph. - Doug