Hi, I don't know if you are following on this actually, but the problem that you stated in December of last year kept puzzling me and I tried to get it cleared after all. For a summary, you can look at http://groups.google.com/group/boost- list/browse_thread/thread/273160db809f1702?fwc=2 Basically, what I understood so far is that the BFS-example seems to be "wrong" because the reduction operation (among others) is not appropriate. However, it seems that it will be fixed soon. Best, Cedric On Wednesday, 8. December 2010 10:49:54 Mattia Lambertini wrote:
Hi, i am new to boost and i'm using the PBGL to write a software that compute some graph analysis. I've installed boost 1.44.0 and openmpi 1.5
I tried to run the breadth first search example located in $BOOST_ROOT/libs/graph_parallel/example
with the graph $BOOST_ROOT/libs/graph/test/weighted_graph.gr
All went well since i figure out that the result is different if i run the algorithm with a different number of processors. Only with one processor the values are corrected.
here's what happens:
mpirun -np 1 ./breadth_first_search.out
graph g { subgraph cluster_0 { label="p0"; n0[label=0]; n1[label=2]; n2[label=1]; n3[label=2]; n4[label=1]; }
n0 -- n2; n1 -- n1; n1 -- n3; n1 -- n4; n2 -- n1; n2 -- n3; n3 -- n4; n4 -- n0; n4 -- n1; }
---------------------
mpirun -np 2 ./breadth_first_search.out
graph g { subgraph cluster_0 { label="p0"; n0[label=0]; n1[label=1]; n2[label=1]; }
n0 -- n2; n1 -- n1; n1 -- n3; n1 -- n4; n2 -- n1; n2 -- n3;
subgraph cluster_1 { label="p1"; n3[label=1]; n4[label=0]; }
n3 -- n4; n4 -- n0; n4 -- n1; }
Is that correct?
From the doc i can't figure out why..