Package elki.index.tree.betula.features

Class BIRCHCF

java.lang.Object

elki.index.tree.betula.features.BIRCHCF

All Implemented Interfaces:

FeatureVector<java.lang.Number>, NumberVector, SpatialComparable, AsClusterFeature, ClusterFeature

public class BIRCHCF
extends java.lang.Object
implements ClusterFeature

Clustering Feature of BIRCH, only for comparison

Since:

0.8.0

Author:

Erich Schubert

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	BIRCHCF.Factory	Factory for making cluster features.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) double[]	ls	Linear sum.
(package private) int	n	Number of objects
(package private) double	ss	Sum of squares (see original thesis, this is a scalar).

Fields inherited from interface elki.data.FeatureVector

TYPE

Fields inherited from interface elki.data.NumberVector

ATTRIBUTE_SEPARATOR, FIELD, FIELD_1D, FIELD_2D, VARIABLE_LENGTH

Constructor Summary

Constructors

Constructor	Description
BIRCHCF(int dimensionality)	Constructor.

Method Summary

Modifier and Type	Method	Description
void	addToStatistics(NumberVector nv)	Add NumberVector to CF
void	addToStatistics(BIRCHCF other)
void	addToStatistics(ClusterFeature other)	Add other CF to CF
double	centroid(int i)	Returns the mean of the specified dimension.
double[][]	covariance()	returns the covariance matrix
int	getDimensionality()	The dimensionality of the vector space where of this FeatureVector of V is an element.
int	getWeight()	Return the weight
double	ls(int i)	Get the linear sum of component i.
void	resetStatistics()	Resets all statistics of CF
double	sumdev()	Returns the total sum of Deviations.
static double	sumOfSquares(NumberVector v)	Compute the sum of squares of a vector.
double	sumOfSquaresOfSums()	Sum over all dimensions of squares of linear sums.
double	sumOfSumOfSquares()	Sum over all dimensions of sums of squares.
double[]	toArray()	Returns a double array copy of this vector.
double	variance()	Returns the total variance.
double	variance(int i)	Returns the variance in the specified dimension.

Methods inherited from class java.lang.Object

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

Methods inherited from interface elki.index.tree.betula.features.ClusterFeature

doubleValue, getCF, longValue

Methods inherited from interface elki.data.FeatureVector

toString

Methods inherited from interface elki.data.NumberVector

byteValue, floatValue, getMax, getMin, getValue, intValue, shortValue

Field Detail

n

int n

Number of objects

ls

double[] ls

Linear sum.

ss

double ss

Sum of squares (see original thesis, this is a scalar).

Constructor Detail

BIRCHCF

public BIRCHCF(int dimensionality)

Constructor.

Parameters:

dimensionality - Dimensionality

Method Detail

addToStatistics

public void addToStatistics(NumberVector nv)

Description copied from interface: ClusterFeature

Add NumberVector to CF

Specified by:

addToStatistics in interface ClusterFeature

Parameters:

nv - NumberVector

addToStatistics

public void addToStatistics(ClusterFeature other)

Description copied from interface: ClusterFeature

Add other CF to CF

Specified by:

addToStatistics in interface ClusterFeature

Parameters:

other - other CF

addToStatistics

public void addToStatistics(BIRCHCF other)

resetStatistics

public void resetStatistics()

Description copied from interface: ClusterFeature

Resets all statistics of CF

Specified by:

resetStatistics in interface ClusterFeature

centroid

public double centroid(int i)

Description copied from interface: ClusterFeature

Returns the mean of the specified dimension.

Specified by:

centroid in interface ClusterFeature

Parameters:

i - dimension

Returns:

mean of this dimension

sumOfSumOfSquares

public double sumOfSumOfSquares()

Sum over all dimensions of sums of squares.

Returns:

Sum of SS

sumOfSquaresOfSums

public double sumOfSquaresOfSums()

Sum over all dimensions of squares of linear sums.

Returns:

Sum of LS

getDimensionality

public int getDimensionality()

Description copied from interface: FeatureVector

The dimensionality of the vector space where of this FeatureVector of V is an element.

Specified by:

getDimensionality in interface FeatureVector<java.lang.Number>

Specified by:

getDimensionality in interface SpatialComparable

Returns:

the number of dimensions of this FeatureVector of V

sumOfSquares

public static double sumOfSquares(NumberVector v)

Compute the sum of squares of a vector.

Parameters:

v - Vector

Returns:

Sum of squares

ls

public double ls(int i)

Get the linear sum of component i.

Parameters:

i - Component

Returns:

linear sum

variance

public double variance(int i)

Description copied from interface: ClusterFeature

Returns the variance in the specified dimension.

Specified by:

variance in interface ClusterFeature

Parameters:

i - dimension

Returns:

variance in this dimension.

getWeight

public int getWeight()

Description copied from interface: ClusterFeature

Return the weight

Specified by:

getWeight in interface ClusterFeature

Returns:

weight of CF

variance

public double variance()

Description copied from interface: ClusterFeature

Returns the total variance.

Specified by:

variance in interface ClusterFeature

Returns:

variance.

sumdev

public double sumdev()

Description copied from interface: ClusterFeature

Returns the total sum of Deviations.

Specified by:

sumdev in interface ClusterFeature

Returns:

Sum of Deviations.

covariance

public double[][] covariance()

Description copied from interface: ClusterFeature

returns the covariance matrix

Specified by:

covariance in interface ClusterFeature

Returns:

covariance

toArray

public double[] toArray()

Description copied from interface: NumberVector

Returns a double array copy of this vector.

Specified by:

toArray in interface NumberVector

Returns:

Copy as double[]