Hello,

I want to calculate the Wiener index of a graph that is stored in igraph format. Although, I'm getting the same error as in the following example:

library('igraph')
library('QuACN')

m = matrix(c(0,1,0,0,0, 1,0,0,0,0, 0,1,0,0,1, 0,0,0,0,1, 0,0,0,1,0), ncol = 5, nrow = 5)
g = graph_from_adjacency_matrix(m)
gNEL = igraph.to.graphNEL(g)
wiener(gNEL)
Error: .validateGraph(g) is not TRUE

Any ideas on what is causing the error?