nl.cwts.networkanalysis

Class LeidenAlgorithm

java.lang.Object

nl.cwts.networkanalysis.CPMClusteringAlgorithm

nl.cwts.networkanalysis.IncrementalCPMClusteringAlgorithm

nl.cwts.networkanalysis.IterativeCPMClusteringAlgorithm

nl.cwts.networkanalysis.LeidenAlgorithm

All Implemented Interfaces:

java.lang.Cloneable, ClusteringAlgorithm, IncrementalClusteringAlgorithm, QualityClusteringAlgorithm

public class LeidenAlgorithm
extends IterativeCPMClusteringAlgorithm

Leiden algorithm.

The Leiden algorithm consists of three phases:

1. local moving of nodes between clusters,
2. refinement of the clusters,
3. aggregation of the network based on the refined clusters, using the non-refined clusters to create an initial clustering for the aggregate network.

These phases are repeated until no further improvements can be made. By default, local moving of nodes is performed using the FastLocalMovingAlgorithm.

Field Summary

Fields

Modifier and Type	Field and Description
static double	DEFAULT_RANDOMNESS Default randomness parameter.
protected IncrementalCPMClusteringAlgorithm	localMovingAlgorithm Local moving algorithm.
protected java.util.Random	random Random number generator.
protected double	randomness Randomness parameter.

Fields inherited from class nl.cwts.networkanalysis.IterativeCPMClusteringAlgorithm

DEFAULT_N_ITERATIONS, nIterations

Fields inherited from class nl.cwts.networkanalysis.CPMClusteringAlgorithm

DEFAULT_RESOLUTION, resolution

Constructor Summary

Constructors

Constructor and Description
LeidenAlgorithm() Constructs a Leiden algorithm.
LeidenAlgorithm(double resolution, int nIterations, double randomness, IncrementalCPMClusteringAlgorithm localMovingAlgorithm, java.util.Random random) Constructs a Leiden algorithm for a specified resolution parameter, number of iterations, randomness parameter, and local moving algorithm.
LeidenAlgorithm(double resolution, int nIterations, double randomness, java.util.Random random) Constructs a Leiden algorithm for a specified resolution parameter, number of iterations, and randomness parameter.
LeidenAlgorithm(java.util.Random random) Constructs a Leiden algorithm.

Method Summary

Modifier and Type	Method and Description
LeidenAlgorithm	clone() Clones the algorithm.
IncrementalCPMClusteringAlgorithm	getLocalMovingAlgorithm() Returns the local moving algorithm.
double	getRandomness() Returns the randomness parameter.
protected boolean	improveClusteringOneIteration(Network network, Clustering clustering) Improves a clustering by performing one iteration of the Leiden algorithm.
void	setLocalMovingAlgorithm(IncrementalCPMClusteringAlgorithm localMovingAlgorithm) Sets the local moving algorithm.
void	setRandomness(double randomness) Sets the randomness parameter.
void	setResolution(double resolution) Sets the resolution parameter.

Methods inherited from class nl.cwts.networkanalysis.IterativeCPMClusteringAlgorithm

getNIterations, improveClustering, setNIterations

Methods inherited from class nl.cwts.networkanalysis.IncrementalCPMClusteringAlgorithm

findClustering

Methods inherited from class nl.cwts.networkanalysis.CPMClusteringAlgorithm

calcQuality, getResolution, removeCluster, removeSmallClustersBasedOnNNodes, removeSmallClustersBasedOnWeight

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_RANDOMNESS

public static final double DEFAULT_RANDOMNESS

Default randomness parameter.

See Also:

Constant Field Values

randomness

protected double randomness

Randomness parameter.

localMovingAlgorithm

protected IncrementalCPMClusteringAlgorithm localMovingAlgorithm

Local moving algorithm.

random

protected java.util.Random random

Random number generator.

Constructor Detail

LeidenAlgorithm

public LeidenAlgorithm()

Constructs a Leiden algorithm.

LeidenAlgorithm

public LeidenAlgorithm(java.util.Random random)

Constructs a Leiden algorithm.

Parameters:

random - Random number generator

LeidenAlgorithm

public LeidenAlgorithm(double resolution,
                       int nIterations,
                       double randomness,
                       java.util.Random random)

Constructs a Leiden algorithm for a specified resolution parameter, number of iterations, and randomness parameter.

Parameters:

resolution - Resolution parameter

nIterations - Number of iterations

randomness - Randomness parameter

random - Random number generator

LeidenAlgorithm

public LeidenAlgorithm(double resolution,
                       int nIterations,
                       double randomness,
                       IncrementalCPMClusteringAlgorithm localMovingAlgorithm,
                       java.util.Random random)

Constructs a Leiden algorithm for a specified resolution parameter, number of iterations, randomness parameter, and local moving algorithm.

Parameters:

resolution - Resolution parameter

nIterations - Number of iterations

randomness - Randomness parameter

localMovingAlgorithm - Local moving algorithm

random - Random number generator

Method Detail

clone

public LeidenAlgorithm clone()

Clones the algorithm.

Overrides:

clone in class CPMClusteringAlgorithm

Returns:

Cloned algorithm

getRandomness

public double getRandomness()

Returns the randomness parameter.

Returns:

Randomness parameter

getLocalMovingAlgorithm

public IncrementalCPMClusteringAlgorithm getLocalMovingAlgorithm()

Returns the local moving algorithm.

Returns:

Local moving algorithm

setResolution

public void setResolution(double resolution)

Sets the resolution parameter. Also sets the resolution parameter for the local moving algorithm.

Overrides:

setResolution in class CPMClusteringAlgorithm

Parameters:

resolution - Resolution parameter

setRandomness

public void setRandomness(double randomness)

Sets the randomness parameter.

Parameters:

randomness - Randomness parameter

setLocalMovingAlgorithm

public void setLocalMovingAlgorithm(IncrementalCPMClusteringAlgorithm localMovingAlgorithm)

Sets the local moving algorithm.

Parameters:

localMovingAlgorithm - Local moving algorithm

improveClusteringOneIteration

protected boolean improveClusteringOneIteration(Network network,
                                                Clustering clustering)

Improves a clustering by performing one iteration of the Leiden algorithm.

The Leiden algorithm consists of three phases:

1. local moving of nodes between clusters,
2. refinement of the clusters,
3. aggregation of the network based on the refined clusters, using the non-refined clusters to create an initial clustering for the aggregate network.

These phases are repeated until no further improvements can be made.

Specified by:

improveClusteringOneIteration in class IterativeCPMClusteringAlgorithm

Parameters:

network - Network

clustering - Clustering

Returns:

Boolean indicating whether the clustering has been improved