bcds.phison.gm
Class AlgebraicConnectivity<V,E>

java.lang.Object
  bcds.phison.gm.GraphMetricBase<V,E>
      bcds.phison.gm.AlgebraicConnectivity<V,E>

All Implemented Interfaces:

GraphMetric<V,E>, WithEnvParams

public class AlgebraicConnectivity<V,E>
extends GraphMetricBase<V,E>
implements GraphMetric<V,E>

Computes the algebraic connectivity of a topology, that is, the second smallest eigenvalue of its Laplacian spectrum. The computation is performed by using the jblas library.

Beware: This implementation does not consider a topology with just one node nor a disconnected topology.

Author:

mmanzano

Constructor Summary

AlgebraicConnectivity()
Default constructor.

AlgebraicConnectivity(SimGraph<V,E> g, Environ env)
Creates a new instance and calls setup to complete the initialization.

Method Summary

float[][]	createLaplacianMatrix() Creates the laplacian matrix of the graph according to Wikipedia: Laplacian Matrix
java.lang.String	getDescription() Returns a string describing the metric, for example, article where it has been published, URL where to find reference implementation, etc.
double	getGraphMetric() Returns the algebraic connectivity of the topology.
java.lang.String	getLabel() Returns "Algebraic connectivity".
boolean	isApplicableTo(MetricTarget m) Returns true if m is MetricTarget.GRAPH.

Methods inherited from class bcds.phison.gm.GraphMetricBase

dump, getEdgeMetric, getEnviron, getEnvParams, getGraph, getGraphMetricStdev, getName, getNodeMetric, run, setup

Methods inherited from class java.lang.Object

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

Methods inherited from interface bcds.phison.gm.GraphMetric

dump, getEdgeMetric, getGraphMetricStdev, getNodeMetric, run, setup

Methods inherited from interface bcds.phison.WithEnvParams

getEnviron, getEnvParams, getName

Constructor Detail

AlgebraicConnectivity

public AlgebraicConnectivity()

Default constructor.

AlgebraicConnectivity

public AlgebraicConnectivity(SimGraph<V,E> g,
                             Environ env)

Creates a new instance and calls setup to complete the initialization.

Method Detail

isApplicableTo

public boolean isApplicableTo(MetricTarget m)

Returns true if m is MetricTarget.GRAPH.

Specified by:

isApplicableTo in interface GraphMetric<V,E>

Overrides:

isApplicableTo in class GraphMetricBase<V,E>

getGraphMetric

public double getGraphMetric()

Returns the algebraic connectivity of the topology.

Beware: This implementation does not consider a topology with just one node nor a disconnected topology.

Specified by:

getGraphMetric in interface GraphMetric<V,E>

Overrides:

getGraphMetric in class GraphMetricBase<V,E>

createLaplacianMatrix

public float[][] createLaplacianMatrix()

Creates the laplacian matrix of the graph according to Wikipedia: Laplacian Matrix

getLabel

public java.lang.String getLabel()

Returns "Algebraic connectivity".

Specified by:

getLabel in interface GraphMetric<V,E>

getDescription

public java.lang.String getDescription()

Description copied from interface: GraphMetric

Returns a string describing the metric, for example, article where it has been published, URL where to find reference implementation, etc.

Specified by:

getDescription in interface GraphMetric<V,E>