# Package opennlp.tools.ml.maxent.quasinewton

- Interface Summary
  Interface | Description
  --- | ---
  Function | Interface for a function
  QNMinimizer.Evaluator | Evaluate quality of training parameters.

- Class Summary
  Class | Description
  --- | ---
  ArrayMath | Deprecated
  LineSearch | Class that performs line search to find minimum
  LineSearch.LineSearchResult | Class to store lineSearch result
  NegLogLikelihood | Evaluate negative log-likelihood and its gradient from DataIndexer.
  ParallelNegLogLikelihood | Evaluate negative log-likelihood and its gradient in parallel
  QNMinimizer | Implementation of L-BFGS which supports L1-, L2-regularization and Elastic Net for solving convex optimization problems.
  QNMinimizer.L2RegFunction | L2-regularized objective function
  QNModel |
  QNTrainer | Maxent model trainer using L-BFGS algorithm.

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