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scale_free_graph(n, alpha=0.41, beta=0.54, gamma=0.05, delta_in=0.2, delta_out=0, create_using=None, seed=None)¶
Returns a scale-free directed graph.
- n (integer) – Number of nodes in graph
- alpha (float) – Probability for adding a new node connected to an existing node chosen randomly according to the in-degree distribution.
- beta (float) – Probability for adding an edge between two existing nodes. One existing node is chosen randomly according the in-degree distribution and the other chosen randomly according to the out-degree distribution.
- gamma (float) – Probability for adding a new node conecgted to an existing node chosen randomly according to the out-degree distribution.
- delta_in (float) – Bias for choosing ndoes from in-degree distribution.
- delta_out (float) – Bias for choosing ndoes from out-degree distribution.
- create_using (graph, optional (default MultiDiGraph)) – Use this graph instance to start the process (default=3-cycle).
- seed (integer, optional) – Seed for random number generator
Create a scale-free graph on one hundred nodes:
>>> G = nx.scale_free_graph(100)
The sum of
gammamust be 1.
 B. Bollobás, C. Borgs, J. Chayes, and O. Riordan, Directed scale-free graphs, Proceedings of the fourteenth annual ACM-SIAM Symposium on Discrete Algorithms, 132–139, 2003.