de.jstacs.classifier.scoringFunctionBased.logPrior
Class LogPrior

java.lang.Object
  de.jstacs.algorithms.optimization.DifferentiableFunction
      de.jstacs.classifier.scoringFunctionBased.logPrior.LogPrior

All Implemented Interfaces:

Function, Storable

Direct Known Subclasses:

DoesNothingLogPrior, SeparateLogPrior, SimpleGaussianSumLogPrior

public abstract class LogPrior
extends DifferentiableFunction
implements Storable

The abstract class for any log-prior used e.g. for maximum supervised posterior optimization.

Author:

Jens Keilwagen

Field Summary

static int

UNKNOWN Sometimes the method getDimensionOfScope() can not return a value.

Constructor Summary

LogPrior()

Method Summary

abstract void	addGradientFor(double[] params, double[] vector) Adds the gradient of the log-prior using the current parameters to a given vector.
double[]	evaluateGradientOfFunction(double[] params) Evaluates the gradient of function at a certain vector (in mathematical sense) x
abstract String	getInstanceName() Returns a short instance name.
abstract LogPrior	getNewInstance() This method returns an empty new instance of the current prior.
void	set(boolean freeParameters, ScoringFunction... funs) Resets all pre-computed values to their initial values using the ScoringFunctions funs
abstract StringBuffer	toXML() Encodes the prior as an XML-representation.

Methods inherited from class de.jstacs.algorithms.optimization.DifferentiableFunction

findOneDimensionalMin

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.jstacs.algorithms.optimization.Function

evaluateFunction, getDimensionOfScope

Field Detail

UNKNOWN

public static final int UNKNOWN

Sometimes the method getDimensionOfScope() can not return a value. In these cases it is recommended to use this constant.

See Also:

Constant Field Values

Constructor Detail

LogPrior

public LogPrior()

Method Detail

addGradientFor

public abstract void addGradientFor(double[] params,
                                    double[] vector)
                             throws EvaluationException

Adds the gradient of the log-prior using the current parameters to a given vector.

Parameters:

params - the parameters

vector - the vector

Throws:

EvaluationException - is thrown if the gradient could not be evaluated

evaluateGradientOfFunction

public final double[] evaluateGradientOfFunction(double[] params)
                                          throws EvaluationException

Description copied from class: DifferentiableFunction

Evaluates the gradient of function at a certain vector (in mathematical sense) x

Specified by:

evaluateGradientOfFunction in class DifferentiableFunction

Parameters:

params - the current vector

Returns:

the elvaluation of the gradient of a function; has dimension getDimensionOfScope()

Throws:

EvaluationException - if there was a mistake in evaluating the gradient

See Also:

Function.getDimensionOfScope()

getNewInstance

public abstract LogPrior getNewInstance()
                                 throws CloneNotSupportedException

This method returns an empty new instance of the current prior. The method works similar to clone, but does not clone ScoringFunctions that may be inside the instance. The ScoringFunctions must be set by an invocation of the method set(boolean, ScoringFunction...).

Returns:

a new empty instance of the prior

Throws:

CloneNotSupportedException

See Also:

set(boolean, ScoringFunction[])

set

public void set(boolean freeParameters,
                ScoringFunction... funs)
         throws Exception

Resets all pre-computed values to their initial values using the ScoringFunctions funs

Parameters:

freeParameters - if true, only the free parameters are used

funs - the ScoringFunctions for the prior

Throws:

Exception - is thrown if the ScoringFunctions could not be set

toXML

public abstract StringBuffer toXML()

Encodes the prior as an XML-representation. It does not encode all information, since the method set has to be invoked after decoding.

Specified by:

toXML in interface Storable

Returns:

the XML-representation;

getInstanceName

public abstract String getInstanceName()

Returns a short instance name.

Returns:

a short instance name