Error in cluster_edge_betweenness

问题

I am using the function cluster_edge_betweenness provided in iGraph, but I run into error Modularity is implemented for undirected graphs only.

g <- read.csv("sample.csv", header = FALSE) 
G <- graph.data.frame(g)
cluster_edge_betweenness(G)

head(g)
> `   V3       V5
   1 614      644
   2 614     3960
   3 614     4156
   4 614     9902
   5 614    11487
   6 614 68400038`

Above are the first few lines of my data. Any advice on how to solve this issue?

来源：https://stackoverflow.com/questions/51792302/error-in-cluster-edge-betweenness