edu.stanford.nlp.ie.hmm
Class DiscriminativeHMMDiffFunction

java.lang.Object
  |
  +--edu.stanford.nlp.ie.hmm.DiscriminativeHMMDiffFunction

All Implemented Interfaces:

DiffFunction, Function

public class DiscriminativeHMMDiffFunction

extends Object

implements DiffFunction

Interface to optimization package for discriminatively learning the structure of an HMM. Right now for testing purposes this just models the function x^2.

Constructor Summary

DiscriminativeHMMDiffFunction()

Method Summary

double[]	derivativeAt(double[] x) Returns the first-derivative vector at the input location.
int	domainDimension() Returns the number of dimensions in the function's domain
static void	main(String[] args) For internal debugging purposes only.
double	valueAt(double[] x) Returns the value of the function at a single point.

Methods inherited from class java.lang.Object

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

Constructor Detail

DiscriminativeHMMDiffFunction

public DiscriminativeHMMDiffFunction()

Method Detail

derivativeAt

public double[] derivativeAt(double[] x)

Returns the first-derivative vector at the input location.

Specified by:

derivativeAt in interface DiffFunction

Parameters:

x - a double[] input vector

Returns:

the vector of first partial derivatives.

domainDimension

public int domainDimension()

Returns the number of dimensions in the function's domain

Specified by:

domainDimension in interface Function

Returns:

the number of domain dimensions

valueAt

public double valueAt(double[] x)

Returns the value of the function at a single point.

Specified by:

valueAt in interface Function

Parameters:

x - a double[] input

Returns:

the function value at the input

main

public static void main(String[] args)

For internal debugging purposes only. Gets a random starting value and uses this class to find the minimum.