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eulerian_circuit¶

eulerian_circuit
(G, source=None)[source]¶ Return the edges of an Eulerian circuit in G.
An Eulerian circuit is a path that crosses every edge in G exactly once and finishes at the starting node.
Parameters:  G (NetworkX Graph or DiGraph) – A directed or undirected graph
 source (node, optional) – Starting node for circuit.
Returns: edges – A generator that produces edges in the Eulerian circuit.
Return type: generator
Raises: NetworkXError
– If the graph is not Eulerian.See also
Notes
Linear time algorithm, adapted from [1]. General information about Euler tours [2].
References
[1] J. Edmonds, E. L. Johnson. Matching, Euler tours and the Chinese postman. Mathematical programming, Volume 5, Issue 1 (1973), 111114. [2] http://en.wikipedia.org/wiki/Eulerian_path Examples
>>> G=nx.complete_graph(3) >>> list(nx.eulerian_circuit(G)) [(0, 2), (2, 1), (1, 0)] >>> list(nx.eulerian_circuit(G,source=1)) [(1, 2), (2, 0), (0, 1)] >>> [u for u,v in nx.eulerian_circuit(G)] # nodes in circuit [0, 2, 1]