The k-core of graph is a maximal subgraph in which each vertex has at least
degree k. The coreness of a vertex is k if it belongs to the k-core but not
to the (k+1)-core.

Usage

coreness(graph, mode = c("all", "out", "in"))

Arguments

graph

The input graph, it can be directed or undirected

mode

The type of the core in directed graphs. Character constant,
possible values: in: in-cores are computed, out: out-cores are
computed, all: the corresponding undirected graph is considered. This
argument is ignored for undirected graphs.

Value

Numeric vector of integer numbers giving the coreness of each
vertex.

Details

The k-core of a graph is the maximal subgraph in which every vertex has at
least degree k. The cores of a graph form layers: the (k+1)-core is always a
subgraph of the k-core.

This function calculates the coreness for each vertex.

References

Vladimir Batagelj, Matjaz Zaversnik: An O(m) Algorithm for Cores
Decomposition of Networks, 2002

Seidman S. B. (1983) Network structure and minimum degree, Social
Networks, 5, 269--287.