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

Returns a tree with a power law degree distribution.

  • n (int) – The number of nodes.
  • gamma (float) – Exponent of the power law.
  • seed (integer, random_state, or None (default)) – Indicator of random number generation state. See Randomness.
  • tries (int) – Number of attempts to adjust the sequence to make it a tree.

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


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).