Define Edge labels based on matching vertex type in R

Question

I have a graph net with two different types (1 and 2) of vertices, appearing n1 and n2 times, respectively:

net %v% "type" <- c(rep("1", n1), rep("2", n2))

We have some edges which were generated randomly with probabilities ps and pd, where ps is the edge probability with a same type (1-1 or 2-2) and pd with a different type (1-2).

I would like to plot this graph such that the edges between same types (i.e. 1-1 or 2-2) have a different color than edges between different types (1-2).

How do I do this? I tried playing around with the %e% operator of the network package, but I'm confused about how to grab the type of the end node of each edge. Thank you!

Answer 1

Do you want that?

from <- sample(1:2, 10, replace = T)
to <- sample(1:2, 10, replace = T)
node <- cbind(from, to)
library(igraph)
net <- graph_from_edgelist(node, directed = F)
edge_color <- function(from_to){
  from_node <- from_to[1]
  to_node <- from_to[2]
  ifelse(from_node == to_node, return("red"), return("blue"))
}
color<- apply(node, 1, edge_color)
plot(net, edge.color=color)