I have 4 connected, simple, undirected graph objects for which I am trying to discover the shortest paths using igraph in R. When I ran the "shortest.paths" routine on the first two, I had no problem, but for the last two, I come up against what appears to be a memory limitation. I have tried the analysis on both my laptop and my desktop, both of which have 1Gb RAM on a Windows platform. For both of these datasets, I get the message: "Error: cannot allocate vector of size ...". The first problem graph has 6593 vertices and 8268 edges. The second one has 8613 vertices and 10649 edges. These do not strike me as inordinately large, but the first two graphs were a bit smaller and the routine worked just fine for them.
Please forgive the basic nature of this question, but will this problem be resolved if I try the analysis on a 2Gb machine? Are there other possible solutions? I have scoured the R manual for information on how to resolve this problem and think that the memory issue may be the problem, but I can't see any other possibilities.
Your help is GREATLY appreciated!
Alisa.
p.s. I can send the .rdata file if anyone is interested in trying it out on their machine.
-- Alisa Coffin, PhD. Candidate Department of Geography
University of Florida Gainesville, FL 32611