When I try to set the color of edges using the edge.color attribute, it doesn't work (I get default grey). However when I put the same attribute in the plot command, it works! What I am doing wrong? (I am using R version 3.4.1 (2017-06-30) -- "Single Candle" on a linux box). Other attributes such as arrow.size and width work fine for me, it is just the color that doesn't!
According to this Rpub tutorial for igraph, https://rpubs.com/kateto/netviz I should be able to do it both ways...
data<-matrix(rexp(25, rate=.1), ncol=5)
# this gives gray default edges, WHY?
# this give blues edges: