Re: [igraph] Plotting an ancestral graph

[Tamas Nepusz]

> Given the information below, is it possible to single out the number in front 
> of the arrow and the number behind the arrow?
I've found this, but I'm not sure if this is the only way or there's a better 
way than that:

> get.edge(g3, 0)
[1] 1 2
> get.edge(g3, 1)
[1] 1 4
...and so on. get.edge(g3, edge_index)[1] gives you the source, get.edge(g3, 
edge_index)[2] gives you the target. Note that igraph indexes edges and 
vertices from zero, not one; also note that this will change some time in the 
future to become compatible with the rest of R. You can start watching this bug 
report in Launchpad if you are interested in when it will change (definitely 
not before igraph 0.6):

https://bugs.launchpad.net/igraph/+bug/595092

-- 
Tamas