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kernighan_lin_bisection(G, partition=None, max_iter=10, weight='weight', seed=None)[source]

Partition a graph into two blocks using the Kernighan–Lin algorithm.

This algorithm paritions a network into two sets by iteratively swapping pairs of nodes to reduce the edge cut between the two sets.

  • G (graph)
  • partition (tuple) – Pair of iterables containing an initial partition. If not specified, a random balanced partition is used.
  • max_iter (int) – Maximum number of times to attempt swaps to find an improvemement before giving up.
  • weight (key) – Edge data key to use as weight. If None, the weights are all set to one.
  • seed (integer, random_state, or None (default)) – Indicator of random number generation state. See Randomness. Only used if partition is None

partition – A pair of sets of nodes representing the bipartition.

Return type:



NetworkXError – If partition is not a valid partition of the nodes of the graph.


[1]Kernighan, B. W.; Lin, Shen (1970). “An efficient heuristic procedure for partitioning graphs.” Bell Systems Technical Journal 49: 291–307. Oxford University Press 2011.