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Last modified: December 2007

URL: http://cxc.harvard.edu/sherpabeta/set_method.sl.html
AHELP for Sherpa 4.0 Beta set_method Context: sl.sherpa

Synopsis

Set the Sherpa optimization method by name

Syntax

set_method( optimization_method );

Description

Set the Sherpa optimization method by name. The available methods are:

Statistic Description
levmar The MINPACK subroutine LMDIF which minimizes the sum of the squares of m nonlinear functions in n variables by a modification of the Levenberg-Marquardt algoritm written Burton S. Garbow, Kenneth E. Hillstrom, Jorge J. More
moncar The implementation of the moncar method is based on the paper by Hedar A-R; Fukushima M. "Hybrid Simulated Annealing and Direct Search Method for Nonlinear Unconstrained Global Optimization", Optimization Methods and Software, Volume 17, Number 5, 1 January 2002, pp. 891-912(22)
neldermead The implementation of the Nelder Mead Simplex direct search is based on the paper: Jeffrey C. Lagarias, James A. Reeds, Margaret H. Wright, Paul E. Wright "Convergence Properties of the Nelder-Mead Simplex Algorithm in Low Dimensions", SIAM Journal on Optimization,Vol. 9, No. 1 (1998), pages 112-147.
simann A simulated annealing search; see Goffe, Ferrier and Rogers, "Global Optimization of Statistical Functions with Simulated Annealing," Journal of Econometrics, vol. 60, no. 1/2, Jan./Feb. 1994, pp. 65-100.
simplex same as the neldermead method

Example

sherpa> set_method("neldermead");

Set the optimization method as the Nelder Mead simplex.

Bugs

See the bugs pages on the Sherpa Beta website for an up-to-date listing of known bugs.

Last modified: December 2007



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