On Mon, Aug 6, 2012 at 5:12 PM, Sam Steingold <[email protected]> wrote: > (no, I am not asking about the simplify function) > I have a directed graph with, say, 100 sources and 100,000 destinations, > and only 5 sources which are also destinations. > I am mostly interested in sources, but the destinations clutter > everything. > I want to "simplify" the graph by dropping all the destinations, but I > want to add a "weighted" link between two sources which have common > destinations. > How do I do that?
I think what you might need is a bipartite projection. In a bipartite (or two-mode) graph, you have two kind of vertices, e.g. sources and destinations. When you create a one-mode projection, you create a graph where two sources are connected if they have a common neighbor among the destinations. (Or the other way.) Check http://igraph.sourceforge.net/doc/R/bipartite.projection.html The number of common neighbors of the two sources is automatically added as an edge weight, if you set the multiplicity argument to TRUE (the default). G. > thanks! > -- > Sam Steingold (http://sds.podval.org/) on Ubuntu 12.04 (precise) X > 11.0.11103000 > http://www.childpsy.net/ http://www.memritv.org > http://truepeace.org http://jihadwatch.org > To be popular with ladies one has to be smart, handsome & rich. Or to be a > cat. > > _______________________________________________ > igraph-help mailing list > [email protected] > https://lists.nongnu.org/mailman/listinfo/igraph-help -- Gabor Csardi <[email protected]> MTA KFKI RMKI _______________________________________________ igraph-help mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/igraph-help
