Package opennlp.tools.ml.maxent.quasinewton

Class QNModel

java.lang.Object

opennlp.tools.ml.model.AbstractModel

opennlp.tools.ml.maxent.quasinewton.QNModel

All Implemented Interfaces:

MaxentModel

public class QNModel
extends AbstractModel

A maximum entropy model which has been trained via the L-BFGS algorithm , which belongs to the group of Quasi Newton (QN) algorithms.

See Also:

• AbstractModel
• MaxentModel
• QNTrainer

Nested Class Summary

Nested classes/interfaces inherited from class opennlp.tools.ml.model.AbstractModel

AbstractModel.ModelType

Constructor Summary

Constructors

Constructor	Description
QNModel(Context[] params, String[] predLabels, String[] outcomeNames)	Initializes a QNModel with the specified parameters, predicate/feature labels, and outcome names.

Method Summary

Modifier and Type	Method	Description
double[]	eval(String[] context)	Evaluates a context.
double[]	eval(String[] context, double[] probs)	Evaluates a context.
double[]	eval(String[] context, float[] values)	Evaluates a context with the specified context values.
int	getNumOutcomes()

Methods inherited from class opennlp.tools.ml.model.AbstractModel

equals, getAllOutcomes, getBestOutcome, getDataStructures, getIndex, getModelType, getOutcome, hashCode

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Details

QNModel

public QNModel(Context[] params,
 String[] predLabels,
 String[] outcomeNames)

Initializes a QNModel with the specified parameters, predicate/feature labels, and outcome names.

Parameters:

params - The parameters of the model.

predLabels - The names of the predicates used in this model.

outcomeNames - The names of the outcomes this model predicts.

Method Details

getNumOutcomes

public int getNumOutcomes()

Specified by:

getNumOutcomes in interface MaxentModel

Overrides:

getNumOutcomes in class AbstractModel

Returns:

Retrieves the number of outcomes for this model.

eval

public double[] eval(String[] context)

Evaluates a context.

Parameters:

context - An array of String names of the contextual predicates which are to be evaluated together.

Returns:

An array of the probabilities for each of the different outcomes, all of which sum to 1.

eval

public double[] eval(String[] context,
 double[] probs)

Evaluates a context.

Parameters:

context - An array of String names of the contextual predicates which are to be evaluated together.

probs - An array which is populated with the probabilities for each of the different outcomes, all of which sum to 1.

Returns:

An array of the probabilities for each of the different outcomes, all of which sum to 1.

eval

public double[] eval(String[] context,
 float[] values)

Evaluates a context with the specified context values.

Parameters:

context - An array of String names of the contextual predicates which are to be evaluated together.

values - The values associated with each context.

Returns:

An array of the probabilities for each of the different outcomes, all of which sum to 1.