Function (Apache OpenNLP Tools 1.9.5 API)
Date: 2026-06-18

opennlp.tools.ml.maxent.quasinewton

## Interface Function

- All Known Implementing Classes:
    NegLogLikelihood, ParallelNegLogLikelihood, QNMinimizer.L2RegFunction

      public interface Function

  Interface for a function

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method and Description
    --- | ---
    `int` | `getDimension()`
    `double[]` | `gradientAt(double[] x)`
    `double` | `valueAt(double[] x)`

- - ### Method Detail

    - #### getDimension

          int getDimension()

    - #### valueAt

          double valueAt(double[] x)

    - #### gradientAt

          double[] gradientAt(double[] x)

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