igraph is a library for creating and manipulating graphs. It is intended to be as powerful (ie. fast) as possible to enable the analysis of large graphs.
The full documentation can be downloaded from the homepage of the library: <http://igraph.org>
You might also try the info pages of igraph if they are installed:
If you think you have found a bug in igraph, feel free to use the mailing list at email@example.com.
Gabor Csardi <firstname.lastname@example.org>,
Tamas Nepusz <email@example.com>