Source code for easygraph.functions.centrality.degree

from easygraph.utils.decorators import *


__all__ = ["degree_centrality", "in_degree_centrality", "out_degree_centrality"]


[docs]@not_implemented_for("multigraph") def degree_centrality(G): """Compute the degree centrality for nodes in a bipartite network. The degree centrality for a node v is the fraction of nodes it is connected to. parameters ---------- G : graph A easygraph graph Returns ------- nodes : dictionary Dictionary of nodes with degree centrality as the value. Notes ----- The degree centrality are normalized by dividing by n-1 where n is number of nodes in G. """ if len(G) <= 1: return {n: 1 for n in G} s = 1.0 / (len(G) - 1.0) centrality = {n: d * s for n, d in (G.degree()).items()} return centrality
[docs]@not_implemented_for("multigraph") @only_implemented_for_Directed_graph def in_degree_centrality(G): """Compute the in-degree centrality for nodes. The in-degree centrality for a node v is the fraction of nodes its incoming edges are connected to. Parameters ---------- G : graph A EasyGraph graph Returns ------- nodes : dictionary Dictionary of nodes with in-degree centrality as values. Raises ------ EasyGraphNotImplemented: If G is undirected. See Also -------- degree_centrality, out_degree_centrality Notes ----- The degree centrality values are normalized by dividing by the maximum possible degree in a simple graph n-1 where n is the number of nodes in G. For multigraphs or graphs with self loops the maximum degree might be higher than n-1 and values of degree centrality greater than 1 are possible. """ if len(G) <= 1: return {n: 1 for n in G} s = 1.0 / (len(G) - 1.0) centrality = {n: d * s for n, d in G.in_degree().items()} return centrality
[docs]@not_implemented_for("multigraph") @only_implemented_for_Directed_graph def out_degree_centrality(G): """Compute the out-degree centrality for nodes. The out-degree centrality for a node v is the fraction of nodes its outgoing edges are connected to. Parameters ---------- G : graph A EasyGraph graph Returns ------- nodes : dictionary Dictionary of nodes with out-degree centrality as values. Raises ------ EasyGraphNotImplemented: If G is undirected. See Also -------- degree_centrality, in_degree_centrality Notes ----- The degree centrality values are normalized by dividing by the maximum possible degree in a simple graph n-1 where n is the number of nodes in G. For multigraphs or graphs with self loops the maximum degree might be higher than n-1 and values of degree centrality greater than 1 are possible. """ if len(G) <= 1: return {n: 1 for n in G} s = 1.0 / (len(G) - 1.0) centrality = {n: d * s for n, d in G.out_degree().items()} return centrality