Package NX :: Module cluster
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Module NX.cluster

Compute clustering coefficients and transitivity of graphs.

Clustering coefficient

For each node find the fraction of possible triangles that are triangles, c_i = triangles_i / (k_i*(k_i-1)/2) where k_i is the degree of node i.

A coefficient for the whole graph is the average C = avg(c_i)

Transitivity

Find the fraction of all possible triangles which are in fact triangles. Possible triangles are identified by the number of "triads" (two edges with a shared vertex)

T = 3*triangles/triads


Function Summary
  average_clustering(G)
Average clustering coefficient for a graph.
  clustering(G, nbunch, **kwds)
Clustering coefficient for each node in nbunch
  transitivity(G)
Transitivity (fraction of transitive triangles) for a graph
  triangles(G, nbunch, **kwds)
Return number of triangles for nbunch of nodes.

Variable Summary
str __author__ = 'Aric Hagberg (hagberg@lanl.gov)\nPieter Sw...
str __credits__ = ''
str __date__ = '$Date: 2005/03/30 23:56:28 $'
str __revision__ = '$Revision: 1.28 $'

Function Details

average_clustering(G)

Average clustering coefficient for a graph.

Note: this is a space saving routine; It might be faster to use clustering to get a list and then take average.

clustering(G, nbunch=None, **kwds)

Clustering coefficient for each node in nbunch

transitivity(G)

Transitivity (fraction of transitive triangles) for a graph

triangles(G, nbunch=None, **kwds)

Return number of triangles for nbunch of nodes. If nbunch is None, then return triangles for every node.

Note: Each triangle is counted three times: once at each vertex.


Variable Details

__author__

Type:
str
Value:
'''Aric Hagberg (hagberg@lanl.gov)
Pieter Swart (swart@lanl.gov)
Dan Schult (dschult@colgate.edu)'''                                    

__credits__

Type:
str
Value:
''                                                                     

__date__

Type:
str
Value:
'$Date: 2005/03/30 23:56:28 $'                                         

__revision__

Type:
str
Value:
'$Revision: 1.28 $'                                                    

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