Catalano.Statistics.Kernels

Class Sigmoid

java.lang.Object

Catalano.Statistics.Kernels.Sigmoid

All Implemented Interfaces:

IMercerKernel<double[]>, java.io.Serializable

public class Sigmoid
extends java.lang.Object
implements IMercerKernel<double[]>

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Sigmoid() Constructs a new Linear Kernel.
Sigmoid(double alpha, double constant) Constructs a new Sigmoid kernel.

Method Summary

Modifier and Type	Method and Description
double	Function(double[] x, double[] y) Sigmoid kernel function.
double	getAlpha() Gets the kernel's alpha.
double	getConstant() Gets the kernel's constant.
void	setAlpha(double alpha) Sets the kernel's alpha.
void	setConstant(double constant) Sets the kernel's intercept term.

Methods inherited from class java.lang.Object

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

Constructor Detail

Sigmoid

public Sigmoid()

Constructs a new Linear Kernel.

Sigmoid

public Sigmoid(double alpha,
               double constant)

Constructs a new Sigmoid kernel.

Parameters:

constant - A constant intercept term. Default is 1.

Method Detail

getConstant

public double getConstant()

Gets the kernel's constant.

Returns:

Kernel's constant.

setConstant

public void setConstant(double constant)

Sets the kernel's intercept term.

Parameters:

constant - Kernel's intercept term. Default: -e

getAlpha

public double getAlpha()

Gets the kernel's alpha.

Returns:

Kernel's alpha.

setAlpha

public void setAlpha(double alpha)

Sets the kernel's alpha.

Parameters:

alpha - Kernel's alpha. Default: 0.01

Function

public double Function(double[] x,
                       double[] y)

Sigmoid kernel function.

Specified by:

Function in interface IMercerKernel<double[]>

Parameters:

x - Vector x in input space.

y - Vector y in input space.

Returns:

Dot product in feature (kernel) space.