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fast_gnp_random_graph(n, p, seed=None, directed=False)[source]

Returns a G_{n,p} random graph, also known as an Erdős-Rényi graph or a binomial graph.

  • n (int) – The number of nodes.
  • p (float) – Probability for edge creation.
  • seed (int, optional) – Seed for random number generator (default=None).
  • directed (bool, optional (default=False)) – If True, this function returns a directed graph.


The G_{n,p} graph algorithm chooses each of the [n (n - 1)] / 2 (undirected) or n (n - 1) (directed) possible edges with probability p.

This algorithm runs in O(n + m) time, where m is the expected number of edges, which equals p n (n - 1) / 2. This should be faster than gnp_random_graph() when p is small and the expected number of edges is small (that is, the graph is sparse).


[1]Vladimir Batagelj and Ulrik Brandes, “Efficient generation of large random networks”, Phys. Rev. E, 71, 036113, 2005.