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Last modified: December 2013

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

get_proj

Context: confidence

Synopsis

Return information regarding the projection method.

Syntax

get_proj()
get_proj_results()
get_proj_opt( [name] )

Description

get_proj

The get_proj command returns the current projection estimation method object.The function accepts no arguments. The returned information is:

  • eps - precision of resulting limits, default=0.01
  • fast - if 'True', the fit optimization method is switched to a faster option to reduce the time per fit; default=False, so that the current method is used
  • max_rstat - maximum possible value of the reduced statistic, default=3
  • maxfits - maximum number of tries to fit the parameter space, default=5
  • maxiters- maximum number of tries to bracket desired limits, before returning, default=200
  • remin - if during search, a new fit statistic is found that is smaller than original best fit, the difference between new and original statistics must be greater than this value, default=0.01
  • sigma - to get 1, 2, or 3-sigma limits, default=1
  • 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
  • tol - tolerance for the fit, default=0.20000000000000001
  • parallel - Boolean to indicate if proj should be parallelized
  • numcores - number of cores to use in parallelization; default is to use all available cores

get_proj_results

The get_proj_results command accesses results from the last time projection was run. The function accepts no arguments. The results include the following attributes:

  • datasets - Data sets in fit
  • methodname - Estimation method name
  • iterfitname - Iterative fitting method name, if one specified
  • fitname - Optimization method name
  • statname - Statistic name
  • sigma - Change in statistic
  • percent - % confidence interval corresponding to sigma
  • parnames - Model parameter names
  • parvals - Model parameter fit values
  • parmins - Model parameter minimum values
  • parmaxes - Model parameter maximum values
  • warnings - Warning messages

get_proj_opt

The get_proj_opt command returns a projection option by name. If the name isn't specified, it returns a dictionary of all options that govern how projection is run.

  • eps - precision of resulting limits, default=0.01
  • fast - if 'True', the fit optimization method is switched to a faster option to reduce the time per fit; default=False, so that the current method is used
  • max_rstat - maximum possible value of the reduced statistic, default=3
  • maxfits - maximum number of tries to fit the parameter space, default=5
  • maxiters- maximum number of tries to bracket desired limits, before returning, default=200
  • remin - if during search, a new fit statistic is found that is smaller than original best fit, the difference between new and original statistics must be greater than this value, default=0.01
  • sigma - to get 1, 2, or 3-sigma limits, default=1
  • 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
  • tol - tolerance for the fit, default=0.20000000000000001
  • parallel - Boolean to indicate if proj should be parallelized
  • numcores - number of cores to use in parallelization; default is to use all available cores

Example 1

sherpa> get_proj()

Return a variable listing of all settings that govern how the projection method calculates confidence limits. Sample output is

name        = projection
soft_limits = False
maxfits     = 5
parallel    = True
numcores   =  2
max_rstat   = 3
maxiters    = 200
eps         = 0.01
fast        = False
remin       = 0.01
tol         = 0.2
sigma       = 1

Example 2

sherpa> get_proj_results()

Return a variable listing of all results from the last time projection was run.

Example 3

sherpa> get_proj_opt("sigma")
1

Return the value of the sigma option, which is "1" in this example.

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_reg_proj, get_reg_unc, int_proj, int_unc, projection, reg_proj, reg_unc, set_conf_opt, set_covar_opt, set_proj_opt
contrib
get_chart_spectrum
data
get_areascal, get_arf, get_arf_plot, get_axes, get_backscal, get_bkg, get_bkg_plot, get_bkg_scale, get_coord, get_counts, get_data, get_data_plot, get_dep, get_dims, get_error, get_exposure, get_grouping, get_indep, get_quality, get_rmf, get_specresp, get_staterror, get_syserror
filtering
get_filter
fitting
calc_stat_info, get_fit, get_stat_info
info
get_default_id, list_stats
methods
get_draws, get_iter_method_name, get_iter_method_opt, get_method
modeling
get_model, get_model_component, get_model_component_image, get_model_component_plot, get_model_plot, get_num_par, get_order_plot, get_par, get_pileup_model, get_response, get_source, get_source_component_image, get_source_component_plot, image_source
plotting
get_split_plot
psfs
get_kernel, get_psf
statistics
get_chisqr_plot, get_delchi_plot, get_prior, get_sampler, get_stat
utilities
get_analysis, get_rate
visualization
get_ratio, get_resid, image_getregion

Last modified: December 2013
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