[igraph] using igraph to calculate PageRank

[Ana Sofia Morais]

Hello,

 

I am having problems using igraph in order to calculate the weighted form of PageRank for the nodes in a weighted graph. Here is the code I am using.

 

library(igraph)

m <- matrix(c(0,0,0,0,0,4,0,0,0,0,0,0,0,0,5,0,0,0,5,0,0,0,0,0,0,0,0,0,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,4,0,0,4,0,3,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,4,4,0,0,0,0,0,0,0), nrow=9, ncol=9)

tm <- t(m)

net = graph.adjacency(tm, mode="directed", weighted=TRUE)

prt = page.rank (net, directed = TRUE, damping = 0.85, weights = NULL)$ vector

 

R returns the following error message:

 

Error in page.rank(net, directed = TRUE, damping = 0.85, weights = NULL) :

  At arpack.c:586 : ARPACK error, Unknown ARPACK error

 

However, this problem does not occur when matrix  m is not transposed.

 

I would be thankful for any suggestions on how to solve this problem.

 

With best wishes,

 

Sofia