Warning

This documents an unmaintained version of NetworkX. Please upgrade to a maintained version and see the current NetworkX documentation.

maximal_independent_set

maximal_independent_set(G, nodes=None)

Return a random maximal independent set guaranteed to contain a given set of nodes.

An independent set is a set of nodes such that the subgraph of G induced by these nodes contains no edges. A maximal independent set is an independent set such that it is not possible to add a new node and still get an independent set.

Parameters:

• G (NetworkX graph) –
• nodes (list or iterable) – Nodes that must be part of the independent set. This set of nodes must be independent.

Returns:

indep_nodes – List of nodes that are part of a maximal independent set.

Return type:

list

Raises:

NetworkXUnfeasible – If the nodes in the provided list are not part of the graph or do not form an independent set, an exception is raised.

Examples

>>> G = nx.path_graph(5)
>>> nx.maximal_independent_set(G) 
[4, 0, 2]
>>> nx.maximal_independent_set(G, [1]) 
[1, 3]

Notes

This algorithm does not solve the maximum independent set problem.