de.lmu.ifi.dbs.elki.math.linearalgebra.pca.weightfunctions

Class ExponentialWeight

java.lang.Object

de.lmu.ifi.dbs.elki.math.linearalgebra.pca.weightfunctions.ExponentialWeight

All Implemented Interfaces:

WeightFunction

public final class ExponentialWeight
extends Object
implements WeightFunction

Exponential Weight function, scaled such that the result it 0.1 at distance == max exp(-2.3025850929940455 * distance/max) This is similar to the Gaussian weight function, except distance/max is not squared. -2.3025850929940455 is log(-.1) to achieve the intended range of 1.0 - 0.1

Author:

Erich Schubert

Constructor Summary

Constructors

Constructor and Description
ExponentialWeight()

Method Summary

Methods

Modifier and Type	Method and Description
double	getWeight(double distance, double max, double stddev) Exponential Weight function. stddev is not used.

Methods inherited from class java.lang.Object

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

Constructor Detail

ExponentialWeight

public ExponentialWeight()

Method Detail

getWeight

public double getWeight(double distance,
               double max,
               double stddev)

Exponential Weight function. stddev is not used.

Specified by:

getWeight in interface WeightFunction

Parameters:

distance - distance of the query point

max - maximum distance of all included points

stddev - standard deviation (i.e. quadratic mean / RMS) of the included points

Returns:

weight for the query point