[igraph] segmenting graphs

[Tom Wright]

Hi,
I'm trying to use iGraph in the R environment and I'm getting confused.
It seems to me that what I want to do should be simple but...

t<-graph.empty()
t<-t+vertices(c('r',LETTERS[1:9]))
t['r',D.vertices[,1],attr='weight']<-1
t['A','B']<-1
t['r','A']<-FALSE

I want to get the subgraph with vertex 'A' as the root, i.e. vertices
{'A','B'}

t['A'] seems to give me the children of A but I'm not sure how to use
this in the induced.subgraph()


Thanks
Tom