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Last modified: December 2013

URL: http://cxc.harvard.edu/sherpa/ahelp/set_method_opt.html
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AHELP for CIAO 4.6 Sherpa v2

set_method_opt

Context: methods

Synopsis

Set the options of the chosen optimization method

Syntax

set_method_opt( optname, val )

Description

The set_method_opt command sets the options for the chosen optimization method. Refer to the ahelp file for each method for a complete description of the options (e.g. "ahelp levmar").

  • optname - optimization method option name
  • val - value for the option

A list of the available options for each method is returned by the get_method_opt command ("ahelp get_method_opt"), e.g.

sherpa> get_method_name()
levmar

sherpa> get_method_opt()
{'epsfcn': 1.1920928955078125e-07,
 'factor': 100.0,
 'ftol': 1.1920928955078125e-07,
 'gtol': 1.1920928955078125e-07,
 'maxfev': None,
 'verbose': 0,
 'xtol': 1.1920928955078125e-07}

Example 1

sherpa> set_method("levmar")
sherpa> set_method_opt("maxfev",750)

Set the "maxfev" option (maximum number of function evaluations) in the levmar method to 750.

Example 2

sherpa> set_method ("neldermead")
sherpa> set_method_opt ("maxfev", 2000)
sherpa> set_method_opt ("verbose", 1)

The optimization method is set to neldermead. The "maxfev" is set to 2000 and the verbosity is set to 1.

Bugs

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

See Also

confidence
set_conf_opt, set_covar_opt, set_proj_opt
data
set_areascal, set_arf, set_backscal, set_bkg, set_coord, set_counts, set_data, set_exposure, set_grouping, set_quality, set_rmf, set_staterror, set_syserror
filtering
set_filter
methods
gridsearch, levmar, list_iter_methods, list_methods, moncar, neldermead, set_iter_method, set_iter_method_opt, set_method
modeling
get_par, set_bkg_model, set_full_model, set_par, set_pileup_model, set_source, set_xsabund, set_xscosmo, set_xsxsect, set_xsxset
statistics
set_prior, set_sampler, set_sampler_opt, set_stat
utilities
set_analysis, set_default_id
visualization
image_setregion

Last modified: December 2013
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