wehub-resource-sync
126 lines
3.1 KiB
Python
126 lines
3.1 KiB
Python
from easygraph.utils.decorators import *
|
|
|
|
|
|
__all__ = ["degree_centrality", "in_degree_centrality", "out_degree_centrality"]
|
|
|
|
|
|
@not_implemented_for("multigraph")
|
|
@hybrid("cpp_degree_centrality")
|
|
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
|
|
|
|
|
|
@not_implemented_for("multigraph")
|
|
@only_implemented_for_Directed_graph
|
|
@hybrid("cpp_in_degree_centrality")
|
|
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
|
|
|
|
|
|
@not_implemented_for("multigraph")
|
|
@only_implemented_for_Directed_graph
|
|
@hybrid("cpp_out_degree_centrality")
|
|
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
|