networkx.algorithms.graphical.is_digraphical¶
-
is_digraphical
(in_sequence, out_sequence)[source]¶ Returns True if some directed graph can realize the in- and out-degree sequences.
- Parameters
in_sequence (list or iterable container) – A sequence of integer node in-degrees
out_sequence (list or iterable container) – A sequence of integer node out-degrees
- Returns
valid – True if in and out-sequences are digraphic False if not.
- Return type
Notes
This algorithm is from Kleitman and Wang 1. The worst case runtime is \(O(s \times \log n)\) where \(s\) and \(n\) are the sum and length of the sequences respectively.
References
- 1
D.J. Kleitman and D.L. Wang Algorithms for Constructing Graphs and Digraphs with Given Valences and Factors, Discrete Mathematics, 6(1), pp. 79-88 (1973)