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networkx.generators.random_graphs.random_powerlaw_tree_sequence

random_powerlaw_tree_sequence(n, gamma=3, seed=None, tries=100)[source]

Returns a degree sequence for a tree with a power law 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 power law distribution until the sequence makes a tree (by checking, for example, that the number of edges is one smaller than the number of nodes).