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# is_graphical¶

is_graphical(sequence, method='eg')[source]

Returns True if sequence is a valid degree sequence.

A degree sequence is valid if some graph can realize it.

Parameters: sequence (list or iterable container) – A sequence of integer node degrees
method : “eg” | “hh”
The method used to validate the degree sequence. “eg” corresponds to the Erdős-Gallai algorithm, and “hh” to the Havel-Hakimi algorithm.
Returns: valid – True if the sequence is a valid degree sequence and False if not. bool

Examples

>>> G = nx.path_graph(4)
>>> sequence = G.degree().values()
>>> nx.is_valid_degree_sequence(sequence)
True


References

Erdős-Gallai
[EG1960], [choudum1986]
Havel-Hakimi
[havel1955], [hakimi1962], [CL1996]