Class QuadraticStddevWeight

  extended by de.lmu.ifi.dbs.elki.math.linearalgebra.pca.weightfunctions.QuadraticStddevWeight
All Implemented Interfaces:
WeightFunction, InspectionUtilFrequentlyScanned

public final class QuadraticStddevWeight
extends Object
implements WeightFunction

Quadratic weight function, scaled using the standard deviation. We needed another scaling here, we chose the cutoff point to be 3*stddev. If you need another value, you have to reimplement this class. max(0.0, 1.0 - (distance/(3*stddev))^2

Field Summary
private static double scaling
          Scaling: at scaling * stddev the function will hit 0.0
Constructor Summary
Method Summary
 double getWeight(double distance, double max, double stddev)
          Evaluate weight function at given parameters. max is ignored.
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail


private static final double scaling
Scaling: at scaling * stddev the function will hit 0.0

See Also:
Constant Field Values
Constructor Detail


public QuadraticStddevWeight()
Method Detail


public double getWeight(double distance,
                        double max,
                        double stddev)
Evaluate weight function at given parameters. max is ignored.

Specified by:
getWeight in interface WeightFunction
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
weight for the query point

Release 0.4.0 (2011-09-20_1324)