Author: luc Date: Tue Mar 13 13:03:21 2007 New Revision: 517839 URL: http://svn.apache.org/viewvc?view=rev&rev=517839 Log: added a section for the optimization package in the user guide
Added: jakarta/commons/proper/math/trunk/xdocs/userguide/optimization.xml (with props) Added: jakarta/commons/proper/math/trunk/xdocs/userguide/optimization.xml URL: http://svn.apache.org/viewvc/jakarta/commons/proper/math/trunk/xdocs/userguide/optimization.xml?view=auto&rev=517839 ============================================================================== --- jakarta/commons/proper/math/trunk/xdocs/userguide/optimization.xml (added) +++ jakarta/commons/proper/math/trunk/xdocs/userguide/optimization.xml Tue Mar 13 13:03:21 2007 @@ -0,0 +1,88 @@ +<?xml version="1.0"?> + +<!-- + 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. + --> + +<?xml-stylesheet type="text/xsl" href="./xdoc.xsl"?> +<!-- $Revision: 480435 $ $Date: 2006-11-29 08:06:35 +0100 (mer., 29 nov. 2006) $ --> +<document url="optimization.html"> + + <properties> + <title>The Commons Math User Guide - Optimization</title> + </properties> + + <body> + <section name="13 Optimization"> + <subsection name="13.1 Overview" href="overview"> + <p> + The optimization package provides simplex-based direct search optimization algorithms. + </p> + <p> + The aim of this package is similar to the aim of the estimation package, but the + algorithms are entirely differents as: + <ul> + <li> + they do not need the partial derivatives of the measurements + with respect to the free parameters + </li> + <li> + they do not rely on residuals-based quadratic cost functions but + handle any cost functions, including non-continuous ones! + </ul> + </p> + </subsection> + <subsection name="13.2 Direct Methods" href="direct"> + <p> + Direct search methods only use cost function values, they don't + need derivatives and don't either try to compute approximation of + the derivatives. According to a 1996 paper by Margaret H. Wright + (<a href="http://cm.bell-labs.com/cm/cs/doc/96/4-02.ps.gz">Direct + Search Methods: Once Scorned, Now Respectable</a>), they are used + when either the computation of the derivative is impossible (noisy + functions, unpredictable dicontinuities) or difficult (complexity, + computation cost). In the first cases, rather than an optimum, a + <em>not too bad</em> point is desired. In the latter cases, an + optimum is desired but cannot be reasonably found. In all cases + direct search methods can be useful. + </p> + <p> + Simplex-based direct search methods are based on comparison of + the cost function values at the vertices of a simplex (which is a + set of n+1 points in dimension n) that is updated by the algorithms + steps. + </p> + <p> + The instances can be built either in single-start or in + multi-start mode. Multi-start is a traditional way to try to avoid + beeing trapped in a local minimum and miss the global minimum of a + function. It can also be used to verify the convergence of an + algorithm. In multi-start mode, the <code>minimizes</code>method + returns the best minimum found after all starts, and the <code>etMinima</code> + method can be used to retrieve all minima from all starts (including the one + already provided by the <code>minimizes</code> method). + </p> + <p> + The package provides two solvers. The first one is the classical + <a href="../apidocs/org/apache/commons/math/optimization/NelderMead.html"> + Nelder-Mead</a> method. The second one is Virginia Torczon's + <a href="../apidocs/org/apache/commons/math/optimization/MultiDirectional.html"> + multi-directional</a> method. + </p> + </subsection> + </section> + </body> +</document> Propchange: jakarta/commons/proper/math/trunk/xdocs/userguide/optimization.xml ------------------------------------------------------------------------------ svn:eol-style = native --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]