Use this if you are using igraph from R
| sample_islands {igraph} | R Documentation | 
Create a number of Erdos-Renyi random graphs with identical parameters, and connect them with the specified number of edges.
sample_islands(islands.n, islands.size, islands.pin, n.inter)
islands.n | 
 The number of islands in the graph.  | 
islands.size | 
 The size of islands in the graph.  | 
islands.pin | 
 The probability to create each possible edge into each island.  | 
n.inter | 
 The number of edges to create between two islands.  | 
An igraph graph.
g <- sample_islands(3, 10, 5/10, 1) oc <- cluster_optimal(g) oc
Samuel Thiriot