Re: [Boost-users] [BGL] premature termination in dijkstra using visitor

Subject: Re: [Boost-users] [BGL] premature termination in dijkstra using visitor
From: Ralf Goertz (R_Goertz_at_[hidden])
Date: 2009-10-07 03:38:31

Andrew Sutton wrote:

> On Tue, Oct 6, 2009 at 10:38 AM, Ralf Goertz
> <R_Goertz_at_[hidden]>wrote:
> 
>> I managed to create a visitor now, however, instead of speeding things
>> up dijkstra_shortest_paths now runs several orders of magnitudes
>> slower! I created the visitor according to the bfs_name_printer
>> example in the BGL User Guide and Reference Book page 11.
>> The code seems to do what I want, all dists are either 0,1,2,3 or
>>
> 
> 
>> numeric_limits<unsigned>::max(). But for a graph with 15000 edges it
>> takes a few ms to run dijkstra without a visitor but with it it takes
>> 14 seconds. What am I doing wrong?
>>
> 
> Are you compiling in debug mode? It can cause dramatic slowdowns with
> the BGL.

No, I use full optimization with g++ version 4.3: "CXXFLAGS=-O3
-Wno-deprecated" is in my Makefile. I also noticed that when I
explicitely use .visitor(default_dijkstra_visitor) or my derived class
without the "void finish_vertex(Vertex u, Graph g)" no harm is done.

In the header files I found the macro BOOST_GRAPH_EVENT_STUB being
applied to the default_bfs_visitor. Do I need to apply it to my derived
class as well?