de.lmu.ifi.dbs.elki.math.linearalgebra.randomprojections

Class AchlioptasRandomProjectionFamily

java.lang.Object

de.lmu.ifi.dbs.elki.math.linearalgebra.randomprojections.AbstractRandomProjectionFamily

de.lmu.ifi.dbs.elki.math.linearalgebra.randomprojections.AchlioptasRandomProjectionFamily

All Implemented Interfaces:

RandomProjectionFamily

@Reference(title="Database-friendly random projections: Johnson-Lindenstrauss with binary coins",
           authors="Dimitris Achlioptas",
           booktitle="Proceedings of the twentieth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems",
           url="http://dx.doi.org/10.1145/375551.375608")
public class AchlioptasRandomProjectionFamily
extends AbstractRandomProjectionFamily

Random projections as suggested by Dimitris Achlioptas. Reference:

Database-friendly random projections: Johnson-Lindenstrauss with binary coins
Dimitris Achlioptas
In: Proceedings of the twentieth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	AchlioptasRandomProjectionFamily.Parameterizer Parameterization class.

Field Summary

Fields

Modifier and Type	Field and Description
private double	sparsity Projection sparsity.

Fields inherited from class de.lmu.ifi.dbs.elki.math.linearalgebra.randomprojections.AbstractRandomProjectionFamily

random

Constructor Summary

Constructors

Constructor and Description
AchlioptasRandomProjectionFamily(double sparsity, RandomFactory random) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
Matrix	generateProjectionMatrix(int idim, int odim) Generate a projection matrix for the given dimensionalities.
Vector	generateProjectionVector(int odim) Generate a random projection vector for the given dimensionality.

Methods inherited from class java.lang.Object

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

Field Detail

sparsity

private double sparsity

Projection sparsity.

Constructor Detail

AchlioptasRandomProjectionFamily

public AchlioptasRandomProjectionFamily(double sparsity,
                                RandomFactory random)

Constructor.

Parameters:

sparsity - Projection sparsity

random - Random number generator.

Method Detail

generateProjectionMatrix

public Matrix generateProjectionMatrix(int idim,
                              int odim)

Description copied from interface: RandomProjectionFamily

Generate a projection matrix for the given dimensionalities.

Parameters:

idim - Input Dimensionality

odim - Output Dimensionality

Returns:

Projection matrix

generateProjectionVector

public Vector generateProjectionVector(int odim)

Description copied from interface: RandomProjectionFamily

Generate a random projection vector for the given dimensionality.

Parameters:

odim - Input Dimensionality

Returns:

Projection vector