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Last modified: December 2010

URL: http://cxc.harvard.edu/sherpa/get_proj.html
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AHELP for CIAO 4.3 Sherpa v1

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 includes:

  • sigma - to get 1, 2, or 3-sigma limits
  • eps - precision of resulting limits
  • maxiters- maximum number of tries to bracket desired limits, before returning
  • 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

The full list of options is described in the "get_proj_opt" section, below.

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
  • fitname - Fitting method name
  • statname - Statistic name
  • sigma - Change in statistic
  • 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 - the method is automatically switched to a faster option to reduce the time per fit, default=True
  • 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=0.01
  • 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

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
max_rstat   = 3
maxiters    = 200
soft_limits = False
eps         = 0.01
fast        = True
maxfits     = 5
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_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_stat
utilities
get_analysis, get_rate
visualization
get_ratio, get_resid, image_getregion

Last modified: December 2010
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