Re: [igraph] R: igraph: decompose.graph: Error: protect(): protection stack overflow

[Tamás Nepusz]

> > which(sc.cl$membership == 0)
>  
> [1] 1 2 92259 280860
>  
> BUT:
> > subgraph(sc.gr (http://sc.gr), which(sc.cl$membership == 0))
>  
> […]
> this is not a weakly connected component!
Unless you are using igraph 0.6, you were probably bitten by the off-by-one 
indexing trap: node indices in igraph start from zero, but which() returns 
1-based indexes, so you have to subtract 1 from the result of which().

--  
T.