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networkx.generators.random_graphs.random_powerlaw_tree

random_powerlaw_tree(n, gamma=3, seed=None, tries=100)

Returns a tree with a power law degree distribution.

Parameters:

• n (int) – The number of nodes.
• gamma (float) – Exponent of the power law.
• seed (int, optional) – Seed for random number generator (default=None).
• tries (int) – Number of attempts to adjust the sequence to make it a tree.

Raises:

NetworkXError – If no valid sequence is found within the maximum number of attempts.

Notes

A trial power law degree sequence is chosen and then elements are swapped with new elements from a powerlaw distribution until the sequence makes a tree (by checking, for example, that the number of edges is one smaller than the number of nodes).