org.biojava.stats.svm

Class RadialBaseKernel

java.lang.Object

org.biojava.stats.svm.NestedKernel

org.biojava.stats.svm.RadialBaseKernel

All Implemented Interfaces:

Serializable, SVMKernel

public class RadialBaseKernel
extends NestedKernel

This kernel computes the radial base kernel that corresponds to a gausian distribution.

The formula for this is exp( -||a - b|| / (2* width ^ 2)). The term a-b can be represented in an arbitrary feature space by using a nested kernel k, and becomes k(a, a) + k(b, b) - 2 * k(a, b).

As k(x, x) is required repeatedly, I suggest using a DiagonalCachingKernel as the immediately nested kernel function.

Author:

Matthew Pocock

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
RadialBaseKernel()
RadialBaseKernel(SVMKernel nested, double width)

Method Summary

Methods

Modifier and Type	Method and Description
double	evaluate(Object a, Object b) Return the dot product of two vectors in an arbitrary feature space.
double	getWidth()
void	setWidth(double width)
String	toString()

Methods inherited from class org.biojava.stats.svm.NestedKernel

getNestedKernel, setNestedKernel

Methods inherited from class java.lang.Object

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

Constructor Detail

RadialBaseKernel

public RadialBaseKernel()

RadialBaseKernel

public RadialBaseKernel(SVMKernel nested,
                double width)

Method Detail

evaluate

public double evaluate(Object a,
              Object b)

Description copied from interface: SVMKernel

Return the dot product of two vectors in an arbitrary feature space. In this implementation, the `vectors' can actually be arbitrary objects.

getWidth

public double getWidth()

setWidth

public void setWidth(double width)

toString

public String toString()

Overrides:

toString in class Object