Class NormalizedPolyKernel

All Implemented Interfaces:
Serializable, CapabilitiesHandler, OptionHandler, RevisionHandler

public class NormalizedPolyKernel extends PolyKernel
The normalized polynomial kernel.
K(x,y) = <x,y>/sqrt(<x,x><y,y>) where <x,y> = PolyKernel(x,y)

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)
 -E <num>
  The Exponent to use.
  (default: 1.0)
 -L
  Use lower-order terms.
  (default: no)
Version:
$Revision: 1.8 $
Author:
Eibe Frank (eibe@cs.waikato.ac.nz)
See Also:
  • Constructor Details

    • NormalizedPolyKernel

      public NormalizedPolyKernel()
      default constructor - does nothing
    • NormalizedPolyKernel

      public NormalizedPolyKernel(Instances dataset, int cacheSize, double exponent, boolean lowerOrder) throws Exception
      Creates a new NormalizedPolyKernel instance.
      Parameters:
      dataset - the training dataset used.
      cacheSize - the size of the cache (a prime number)
      exponent - the exponent to use
      lowerOrder - whether to use lower-order terms
      Throws:
      Exception - if something goes wrong
  • Method Details

    • globalInfo

      public String globalInfo()
      Returns a string describing the kernel
      Overrides:
      globalInfo in class PolyKernel
      Returns:
      a description suitable for displaying in the explorer/experimenter gui
    • eval

      public double eval(int id1, int id2, Instance inst1) throws Exception
      Computes the result of the kernel function for two instances. If id1 == -1, eval use inst1 instead of an instance in the dataset. Redefines the eval function of PolyKernel.
      Overrides:
      eval in class CachedKernel
      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:
      Exception - if something goes wrong
    • setExponent

      public void setExponent(double value)
      Sets the exponent value (must be different from 1.0).
      Overrides:
      setExponent in class PolyKernel
      Parameters:
      value - the exponent value
    • toString

      public String toString()
      returns a string representation for the Kernel
      Overrides:
      toString in class PolyKernel
      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 PolyKernel
      Returns:
      the revision