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Last modified: December 2013

URL: http://cxc.harvard.edu/sherpa/ahelp/set_covar_opt.html
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AHELP for CIAO 4.9 Sherpa v1

set_covar_opt

Context: confidence

Synopsis

Set the options for covariance

Syntax

set_covar_opt( name, val )

Description

The set_covar_opt command sets the options for covariance.

  • name - covariance option name
  • val - value for the option

A list of the available options is returned by the get_covar_opt command ("ahelp get_covar_opt"), e.g.

{'eps': 0.01, 'maxiters': 200, 'sigma': 1, 'soft_limits': False}
  • sigma - to get 1, 2, or 3-sigma limits, default=1
  • eps - precision of resulting limits, default=0.01
  • maxiters- maximum number of tries to bracket desired limits, before returning, default=200
  • soft_limits - a switch which allows the search to go all the way out to the hard parameter limits; if switched on, the search will be restricted to occur within the soft limits, which can be changed by the user, default=False

Example

sherpa> print get_covar_opt()
sherpa> set_covar_opt ("maxiters", 400)
sherpa> set_covar_opt ("sigma", 3)

Check the current covariance settings. Change the "maxiters" value to 400 and the "sigma" value to 3 for the next run of covariance.

Bugs

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

See Also

confidence
conf, covariance, get_conf, get_covar, get_int_proj, get_int_unc, get_proj, get_reg_proj, get_reg_unc, int_proj, int_unc, projection, reg_proj, reg_unc, set_conf_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
set_iter_method, set_iter_method_opt, set_method, set_method_opt
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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