Hi all, I'm analysing an e-mail network. I loaded the following information in a directed igraph: *Vertex* types: person, e-mail V(g)[ type == "person" ] V(g)[ type == "email" ] *Edge* types: sends, receives E(g)[ type == "send" ] E(g)[ type == "receive" ] So for example: John --send--> email1 --receive--> Mary John --send--> email2 --receive--> Mary Mary --send--> email3 --receive--> John I would like to generate a summary of the e-mail activity, with edges with an attribute representing the number of emails: John --2--> Mary Mary --1--> John I tried to do this, but I haven't figured it out yet. I managed to get in/out edges for each letter, but then I don't know what to do to hold a count. lapply(V(g)[type=="email"], function(e){ outedges = V(g) [ from(e) ] print(outedges) inedges = V(g) [ to(e) ] print(inedges) }) I just started using igraph, and I find even basic operations quite difficult to carry out. :-/ How would I go about to do that? Thanks, Mulone -- View this message in context: http://r.789695.n4.nabble.com/igraph-Counting-edges-for-each-vertex-tp4669613.html Sent from the R help mailing list archive at Nabble.com.