NegLogLikelihood (Apache OpenNLP Tools 2.1.0 API)

java.lang.Object
- opennlp.tools.ml.maxent.quasinewton.NegLogLikelihood

All Implemented Interfaces:

Function

Direct Known Subclasses:

ParallelNegLogLikelihood
```
public class NegLogLikelihood
extends Object
implements Function
```
Evaluate negative log-likelihood and its gradient from DataIndexer.

Constructor Summary

Constructors
Constructor Description

NegLogLikelihood(DataIndexer indexer)

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`int`	`getDimension()`
`double[]`	`getInitialPoint()`
`double[]`	`gradientAt(double[] x)`	Compute gradient
`double`	`valueAt(double[] x)`	Negative log-likelihood

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

- Constructor Detail
  - NegLogLikelihood
```
public NegLogLikelihood(DataIndexer indexer)
```
- Method Detail
  - getDimension
```
public int getDimension()
```
    Specified by:
    
    getDimension in interface Function
  - getInitialPoint
```
public double[] getInitialPoint()
```
  - valueAt
```
public double valueAt(double[] x)
```
    Negative log-likelihood
    
    Specified by:
    
    valueAt in interface Function
  - gradientAt
```
public double[] gradientAt(double[] x)
```
    Compute gradient
    
    Specified by:
    
    gradientAt in interface Function