Is a degree sequence graphical?
Determine whether the given vertex degrees (in- and out-degrees for directed graphs) can be reliazed in a simple graph, i.e. a graph without multiple or loop edges.
is_graphical(out.deg, in.deg = NULL)
Integer vector, the degree sequence for undirected graphs, or the out-degree sequence for directed graphs.
NULLor an integer vector. For undireted graphs, it should be
NULL. For directed graphs it specifies the in-degrees.
A logical scalar.
Hakimi SL: On the realizability of a set of integers as degrees of the vertices of a simple graph. J SIAM Appl Math 10:496-506, 1962.
PL Erdos, I Miklos and Z Toroczkai: A simple Havel-Hakimi type algorithm to realize graphical degree sequences of directed graphs. The Electronic Journal of Combinatorics 17(1):R66, 2010.
Other graphical degree sequences