Hi all Is there any systematic way to compute all possible paths, first-order loops and j-th order loops between two given nodes in a flowgraph (directed graph with cycles) - preferably using the igraph library in R? I have checked the igraph documentation but I can't figure out any direct and systematic way to do so. Any ideas? I use the following definitions from Butler, R. and A. Huzurbazar (1997). Stochastic Network Models for Survival Analysis. Journal of the American Statistical Association 92 (437), 246-257. - A path from node i to j is any possible sequence of nodes from i to j which does not pass through any intermediate node more than once. - A first-order loop is any closed path in the flowgraph that returns to the initial node of the loop without passing through any intermediate node more than once. - A jth-order loop consists of j nontouching first-order loops.
For example, in the flowgraph below http://n4.nabble.com/file/n2125321/flowgraph_subsume.jpg there are 18 paths between nodes 1 and a: - 1a; - 12a, 124a, 1243a, 1245a, 12436a, 124365a, 12456a, 124563a; - 13a, 134a, 136a, 1342a, 1345a, 13456a, 1365a, 13654a, 136542a. 3 first-order loops: - 12431, 1245631, 45634; and no loops of order two or more. Thanks in advance jcano -- View this message in context: http://r.789695.n4.nabble.com/All-possible-paths-between-two-nodes-in-a-flowgraph-using-igraphs-tp2125321p2125321.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
