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* http://www.apache.org/licenses/LICENSE-2.0
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/**
* <p>
* Generally, optimizers are algorithms that will either
* {@link org.apache.commons.math3.optim.nonlinear.scalar.GoalType#MINIMIZE minimize} or
* {@link org.apache.commons.math3.optim.nonlinear.scalar.GoalType#MAXIMIZE maximize}
* a scalar function, called the
* {@link org.apache.commons.math3.optim.nonlinear.scalar.ObjectiveFunction <em>objective
* function</em>}.
* <br/>
* For some scalar objective functions the gradient can be computed (analytically
* or numerically). Algorithms that use this knowledge are defined in the
* {@link org.apache.commons.math3.optim.nonlinear.scalar.gradient} package.
* The algorithms that do not need this additional information are located in
* the {@link org.apache.commons.math3.optim.nonlinear.scalar.noderiv} package.
* </p>
*
* <p>
* Some problems are solved more efficiently by algorithms that, instead of an
* objective function, need access to a
* {@link org.apache.commons.math3.optim.nonlinear.vector.ModelFunction
* <em>model function</em>}: such a model predicts a set of values which the
* algorithm tries to match with a set of given
* {@link org.apache.commons.math3.optim.nonlinear.vector.Target target values}.
* Those algorithms are located in the
* {@link org.apache.commons.math3.optim.nonlinear.vector} package.
* <br/>
* Algorithms that also require the
* {@link org.apache.commons.math3.optim.nonlinear.vector.ModelFunctionJacobian
* Jacobian matrix of the model} are located in the
* {@link org.apache.commons.math3.optim.nonlinear.vector.jacobian} package.
* <br/>
* The {@link org.apache.commons.math3.optim.nonlinear.vector.jacobian.AbstractLeastSquaresOptimizer
* non-linear least-squares optimizers} are a specialization of the the latter,
* that minimize the distance (called <em>cost</em> or <em>χ<sup>2</sup></em>)
* between model and observations.
* <br/>
* For cases where the Jacobian cannot be provided, a utility class will
* {@link org.apache.commons.math3.optim.nonlinear.scalar.LeastSquaresConverter
* convert} a (vector) model into a (scalar) objective function.
* </p>
*
* <p>
* This package provides common functionality for the optimization algorithms.
* Abstract classes ({@link org.apache.commons.math3.optim.BaseOptimizer} and
* {@link org.apache.commons.math3.optim.BaseMultivariateOptimizer}) contain
* boiler-plate code for storing {@link org.apache.commons.math3.optim.MaxEval
* evaluations} and {@link org.apache.commons.math3.optim.MaxIter iterations}
* counters and a user-defined
* {@link org.apache.commons.math3.optim.ConvergenceChecker convergence checker}.
* </p>
*
* <p>
* For each of the optimizer types, there is a special implementation that
* wraps an optimizer instance and provides a "multi-start" feature: it calls
* the underlying optimizer several times with different starting points and
* returns the best optimum found, or all optima if so desired.
* This could be useful to avoid being trapped in a local extremum.
* </p>
*/
package org.apache.commons.math3.optim;