weka.classifiers.functions.supportVector

Class RBFKernel

java.lang.Object

weka.classifiers.functions.supportVector.Kernel

weka.classifiers.functions.supportVector.CachedKernel

weka.classifiers.functions.supportVector.RBFKernel

All Implemented Interfaces:

Serializable, CapabilitiesHandler, OptionHandler, RevisionHandler

Direct Known Subclasses:

MIRBFKernel

public class RBFKernel
extends CachedKernel

The RBF kernel. K(x, y) = e^-(gamma * <x-y, x-y>^2)

Valid options are:

 -D
  Enables debugging output (if available) to be printed.
  (default: off)

 -no-checks
  Turns off all checks - use with caution!
  (default: checks on)

 -C <num>
  The size of the cache (a prime number), 0 for full cache and 
  -1 to turn it off.
  (default: 250007)

 -G <num>
  The Gamma parameter.
  (default: 0.01)

Version:

$Revision: 5518 $

Author:

Eibe Frank ([email protected]), Shane Legg ([email protected]) (sparse vector code), Stuart Inglis ([email protected]) (sparse vector code), J. Lindgren (jtlindgr{at}cs.helsinki.fi) (RBF kernel)

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
RBFKernel() default constructor - does nothing.
RBFKernel(Instances data, int cacheSize, double gamma) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	buildKernel(Instances data) builds the kernel with the given data.
String	gammaTipText() Returns the tip text for this property
Capabilities	getCapabilities() Returns the Capabilities of this kernel.
double	getGamma() Gets the gamma value.
String[]	getOptions() Gets the current settings of the Kernel.
String	getRevision() Returns the revision string.
String	globalInfo() Returns a string describing the kernel
Enumeration	listOptions() Returns an enumeration describing the available options.
void	setGamma(double value) Sets the gamma value.
void	setOptions(String[] options) Parses a given list of options.
String	toString() returns a string representation for the Kernel

Methods inherited from class weka.classifiers.functions.supportVector.CachedKernel

cacheSizeTipText, clean, eval, getCacheSize, numCacheHits, numEvals, setCacheSize

Methods inherited from class weka.classifiers.functions.supportVector.Kernel

checksTurnedOffTipText, debugTipText, forName, getChecksTurnedOff, getDebug, makeCopies, makeCopy, setChecksTurnedOff, setDebug

Methods inherited from class java.lang.Object

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

Constructor Detail

RBFKernel

public RBFKernel()

default constructor - does nothing.

RBFKernel

public RBFKernel(Instances data,
         int cacheSize,
         double gamma)
          throws Exception

Constructor. Initializes m_kernelPrecalc[].

Parameters:

data - the data to use

cacheSize - the size of the cache

gamma - the bandwidth

Throws:

Exception - if something goes wrong

Method Detail

globalInfo

public String globalInfo()

Returns a string describing the kernel

Specified by:

globalInfo in class Kernel

Returns:

a description suitable for displaying in the explorer/experimenter gui

listOptions

public Enumeration listOptions()

Returns an enumeration describing the available options.

Specified by:

listOptions in interface OptionHandler

Overrides:

listOptions in class CachedKernel

Returns:

an enumeration of all the available options.

setOptions

public void setOptions(String[] options)
                throws Exception

Parses a given list of options.

Valid options are:

 -D
  Enables debugging output (if available) to be printed.
  (default: off)

 -no-checks
  Turns off all checks - use with caution!
  (default: checks on)

 -C <num>
  The size of the cache (a prime number), 0 for full cache and 
  -1 to turn it off.
  (default: 250007)

 -G <num>
  The Gamma parameter.
  (default: 0.01)

Specified by:

setOptions in interface OptionHandler

Overrides:

setOptions in class CachedKernel

Parameters:

options - the list of options as an array of strings

Throws:

Exception - if an option is not supported

getOptions

public String[] getOptions()

Gets the current settings of the Kernel.

Specified by:

getOptions in interface OptionHandler

Overrides:

getOptions in class CachedKernel

Returns:

an array of strings suitable for passing to setOptions

setGamma

public void setGamma(double value)

Sets the gamma value.

Parameters:

value - the gamma value

getGamma

public double getGamma()

Gets the gamma value.

Returns:

the gamma value

gammaTipText

public String gammaTipText()

Returns the tip text for this property

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

getCapabilities

public Capabilities getCapabilities()

Returns the Capabilities of this kernel.

Specified by:

getCapabilities in interface CapabilitiesHandler

Overrides:

getCapabilities in class Kernel

Returns:

the capabilities of this object

See Also:

Capabilities

buildKernel

public void buildKernel(Instances data)
                 throws Exception

builds the kernel with the given data. Initializes the kernel cache. The actual size of the cache in bytes is (64 * cacheSize).

Overrides:

buildKernel in class CachedKernel

Parameters:

data - the data to base the kernel on

Throws:

Exception - if something goes wrong

toString

public String toString()

returns a string representation for the Kernel

Overrides:

toString in class Object

Returns:

a string representaiton of the kernel

getRevision

public String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Overrides:

getRevision in class Kernel

Returns:

the revision