I have U.S. trade data between cities. I have attribute data on both the cities (nodes) and the trade (edges).
Consider the following graph:
library(igraph)
gg <- graph.atlas(711)
V(gg)$name <- 1:7
V(gg)$city <- c("BOISE","NEW YORK","NEW YORK","BOISE","BOISE","LA","LA")
V(gg)$color <- ifelse(V(gg)$city=="BOISE", "orange","yellow")
gg <- delete.edges(gg, E(gg,P=c(1,2,2,3,2,7,7,6,7,3,3,4,3,5,4,5,5,6,6,1)))
gg <- add.edges(gg,c(1,4,4,5,5,1),attr=list(trade=1))
gg <- add.edges(gg,c(7,5,5,4,4,7),attr=list(trade=2))
gg <- add.edges(gg,c(7,3,3,5,5,7),attr=list(trade=3))
gg <- add.edges(gg,c(2,7,7,6,6,2),attr=list(trade=4))
gg <- add.edges(gg,c(6,4),attr=list(trade=5))
plot(gg, edge.label=E(gg)$trade)
The generates the following:
From this, I want to export an edgelist that includes the edge attribute to a text file.
For instance:
[CITY 1], [CITY 2], [TRADE]
Any help on how I can do this? It seems easy, but I am really stuck.