java.lang.Object
- weka.classifiers.functions.supportVector.Kernel
- - weka.classifiers.functions.supportVector.CachedKernel

All Implemented Interfaces:

java.io.Serializable, CapabilitiesHandler, OptionHandler, RevisionHandler

Direct Known Subclasses:

PolyKernel, Puk, RBFKernel
```
public abstract class CachedKernel
extends Kernel
```
Base class for RBFKernel and PolyKernel that implements a simple LRU. (least-recently-used) cache if the cache size is set to a value > 0. Otherwise it uses a full cache.

Version:

$Revision: 4549 $

Author:

Eibe Frank (eibe@cs.waikato.ac.nz), Shane Legg (shane@intelligenesis.net) (sparse vector code), Stuart Inglis (stuart@reeltwo.com) (sparse vector code), J. Lindgren (jtlindgr{at}cs.helsinki.fi) (RBF kernel), Steven Hugg (hugg@fasterlight.com) (refactored, LRU cache), Bernhard Pfahringer (bernhard@cs.waikato.ac.nz) (full cache)

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor Description

CachedKernel()
default constructor - does nothing.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`buildKernel(Instances data)`	builds the kernel with the given data.
`java.lang.String`	`cacheSizeTipText()`	Returns the tip text for this property
`void`	`clean()`	Frees the cache used by the kernel.
`double`	`eval(int id1, int id2, Instance inst1)`	Implements the abstract function of Kernel using the cache.
`int`	`getCacheSize()`	Gets the size of the cache
`java.lang.String[]`	`getOptions()`	Gets the current settings of the Kernel.
`java.util.Enumeration`	`listOptions()`	Returns an enumeration describing the available options.
`int`	`numCacheHits()`	Returns the number of cache hits on dot products.
`int`	`numEvals()`	Returns the number of time Eval has been called.
`void`	`setCacheSize(int value)`	Sets the size of the cache to use (a prime number)
`void`	`setOptions(java.lang.String[] options)`	Parses a given list of options.

Methods inherited from class weka.classifiers.functions.supportVector.Kernel
checksTurnedOffTipText, debugTipText, forName, getCapabilities, getChecksTurnedOff, getDebug, getRevision, globalInfo, makeCopies, makeCopy, setChecksTurnedOff, setDebug

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - CachedKernel
```
public CachedKernel()
```
    default constructor - does nothing.
- Method Detail
  - listOptions
```
public java.util.Enumeration listOptions()
```
    Returns an enumeration describing the available options.
    
    Specified by:
    
    listOptions in interface OptionHandler
    
    Overrides:
    
    listOptions in class Kernel
    
    Returns:
    
    an enumeration of all the available options.
  - setOptions
```
public void setOptions(java.lang.String[] options)
                throws java.lang.Exception
```
    Parses a given list of options.
    
    Specified by:
    
    setOptions in interface OptionHandler
    
    Overrides:
    
    setOptions in class Kernel
    
    Parameters:
    
    options - the list of options as an array of strings
    
    Throws:
    
    java.lang.Exception - if an option is not supported
  - getOptions
```
public java.lang.String[] getOptions()
```
    Gets the current settings of the Kernel.
    
    Specified by:
    
    getOptions in interface OptionHandler
    
    Overrides:
    
    getOptions in class Kernel
    
    Returns:
    
    an array of strings suitable for passing to setOptions
  - eval
```
public double eval(int id1,
                   int id2,
                   Instance inst1)
            throws java.lang.Exception
```
    Implements the abstract function of Kernel using the cache. This method uses the evaluate() method to do the actual dot product.
    
    Specified by:
    
    eval in class Kernel
    
    Parameters:
    
    id1 - the index of the first instance in the dataset
    
    id2 - the index of the second instance in the dataset
    
    inst1 - the instance corresponding to id1 (used if id1 == -1)
    
    Returns:
    
    the result of the kernel function
    
    Throws:
    
    java.lang.Exception - if something goes wrong
  - numEvals
```
public int numEvals()
```
    Returns the number of time Eval has been called.
    
    Specified by:
    
    numEvals in class Kernel
    
    Returns:
    
    the number of kernel evaluation.
  - numCacheHits
```
public int numCacheHits()
```
    Returns the number of cache hits on dot products.
    
    Specified by:
    
    numCacheHits in class Kernel
    
    Returns:
    
    the number of cache hits.
  - clean
```
public void clean()
```
    Frees the cache used by the kernel.
    
    Specified by:
    
    clean in class Kernel
  - setCacheSize
```
public void setCacheSize(int value)
```
    Sets the size of the cache to use (a prime number)
    
    Parameters:
    
    value - the size of the cache
  - getCacheSize
```
public int getCacheSize()
```
    Gets the size of the cache
    
    Returns:
    
    the cache size
  - cacheSizeTipText
```
public java.lang.String cacheSizeTipText()
```
    Returns the tip text for this property
    
    Returns:
    
    tip text for this property suitable for displaying in the explorer/experimenter gui
  - buildKernel
```
public void buildKernel(Instances data)
                 throws java.lang.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 Kernel
    
    Parameters:
    
    data - the data to base the kernel on
    
    Throws:
    
    java.lang.Exception - if something goes wrong

Class CachedKernel

Constructor Summary

Method Summary

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

Methods inherited from class java.lang.Object

Constructor Detail

CachedKernel

Method Detail

listOptions

setOptions

getOptions

eval

numEvals

numCacheHits

clean

setCacheSize

getCacheSize

cacheSizeTipText

buildKernel