vertex labels in igraph from adjacency matrix
Mark, graph.adjacency always preserves the order of the vertices, so the vertex at row/column 1 will be vertex #0 in the igraph graph, etc. I'll document this in a minute. This means that you can always do g <- graph.adjacency(A) V(g)$name <- colnames(A) But i completely agree that this should be done by default, i'll do that in the near future. Btw, weighted shortest path calculation (= where the edges have weights or capacities) is only implemented in the development version of igraph. Just in case you're looking for that. Best, Gabor
On Wed, Mar 05, 2008 at 01:39:41AM -0500, Mark W Kimpel wrote:
I am getting some unexpected results from some functions of igraph and
it is possible that I am misinterpreting the vertex numbers. Eg., the
max betweenness measure seems to be from a vertex that is not connected
to a single other vertex. Below if my code snippet:
require(igraph)
my.graph <- graph.adjacency(adjmatrix = my.adj.matrix, mode=c("undirected"))
most.between.vert <- colnames(my.adj.matrix)[which(betweenness(graph =
my.graph, v=V(my.graph), directed = FALSE) == max(betweenness(graph =
my.graph, v=V(my.graph), directed = FALSE))) + 1]
sum(my.adj.matrix[most.between.vertext,])
0
Is there a way to automatically set the vertex name attributes from the
row and colnames of the inputted adjacency matrix to graph.adjacency?
This would seem like an intuitive feature, but I can't find it
documented. In the absence of this feature, how can I make sure that I
am setting the vertex name attributes correctly?
--
Mark W. Kimpel MD ** Neuroinformatics ** Dept. of Psychiatry
Indiana University School of Medicine
15032 Hunter Court, Westfield, IN 46074
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Csardi Gabor <csardi at rmki.kfki.hu> UNIL DGM