GetModularity

GetModularity(Graph, NIdV, GEdges=-1)

Computes the modularity score of a set of node ids NIdV in Graph. The function runs much faster if the number of edges in Graph is provided in the optional GEdges parameter.

Parameters:

  • Graph: graph (input)

    A Snap.py graph or a network.

  • NIdV: TIntV, a vector of ints (input)

    The set of nodes ids from which the modularity score will be computed.

  • GEdges: int (input)

    Optional parameter indicating number of edges in the graph which speeds up the function execution if provided. Note: if GEdges is not equal to the number of edges in the graph, then the computed modularity score will be incorrect.

Return value:

  • float

    The modularity score computed from the provided graph and set of node ids.

The following example shows how to calculate Modularity scores for the first 10 nodes in TNGraph, TUNGraph, and TNEANet:

import snap

Nodes = snap.TIntV()
for nodeId in range(10):
    Nodes.Add(nodeId)

Graph = snap.GenRndGnm(snap.PNGraph, 100, 1000)
print snap.GetModularity(Graph, Nodes, 1000)

UGraph = snap.GenRndGnm(snap.PUNGraph, 100, 1000)
print snap.GetModularity(UGraph, Nodes, 1000)

Network = snap.GenRndGnm(snap.PNEANet, 100, 1000)
print snap.GetModularity(Network, Nodes, 1000)