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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* 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>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>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>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.
*/
package org.apache.commons.math3.optim;
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