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Last modified: December 2006

URL: http://cxc.harvard.edu/ciao3.4/get.html
Hardcopy (PDF): A4 | Letter
AHELP for CIAO 3.4 get Context: sherpa

Synopsis

Summary of Sherpa/S-Lang module functions that retrieve settings or data.

Description

The get functions of the Sherpa/S-Lang module:

  • Retrieve numerical data from Sherpa so that, e.g., they may be manipulated using S-Lang operators and/or functions. (These data may be put back into Sherpa using analogous set functions.)
  • Retrieve Sherpa settings. (Quantities may be set using analogous set functions.)

Note that not all get functions have set function analogues: for instance, while it makes sense to retrieve, change, and set estimated errors, it makes little sense to put new arrays of residuals or predicted model amplitudes into Sherpa.

Summary of Sherpa/S-Lang Module set Functions

Name Description
get_data | get_back Retrieves amplitudes of source and background datasets
get_fluxed_spectrum | get_back Retrieve a fluxed spectrum (counts divided by ARF)
get_errors | get_berrors Retrieves error estimates of source and background datasets
get_syserrors | get_bsyserrors Retrieves systematic errors of source and background datasets
get_weights | get_bweights Retrieves statistical weights for source and background datasets
get_mcounts | get_bmcounts Retrieves predicted source and background model counts amplitudes
get_residuals | get_bresiduals Retrieves the fit residuals for source and background datasets
get_delchi | get_bdelchi Retrieves the fit sigma residuals for source and background datasets
get_ratio | get_bratio Retrieves the ratio of data to model for source and background datasets
get_statistics | get_bstatistics Retrieves the contribution to the current statistic value from each bin, for source and background datasets
get_source | get_bg Retrieves predicted source and background model photon amplitudes
get_groups | get_bgroups Retrieves grouping arrays associated with source and background dataset
get_quality | get_bquality Retrieves quality arrays associated with source and background dataset
get_filter | get_bfilter Retrieves filter arrays associated with source and background datasets
get_axes | get_baxes Retrieves the energy/wavelength/channel grid of source and background datasets
get_energy_axes | get_energy_baxes Retrieves the energy grid of source and background datasets
get_wave_axes | get_wave_baxes Retrieves the wavelength grid of source and background datasets
get_raw_axes | get_raw_baxes Retrieves the raw channel grid of source and background datasets
get_photon_axes | get_bphoton_axes Retrieves photon-space grids over which models are evaluated
get_photon_energy_axes | get_photon_energy_baxes Retrieves photon-space energy grids over which models are evaluated
get_photon_wave_axes | get_photon_wave_baxes Retrieves photon-space wavelength grids over which models are evaluated
get_arf_axes | get_arf_baxes Retrieves the energy/wavelength grid of an ARF associated with source and background datasets
get_analysis Retrieves the current analysis setting.
get_coord Retrieves the current coord setting.
get_fit | get_goodness Retrieves information about the quality of a fit
get_statistic | get_bstatistic Retrieves the current value of the statistic comparing source and background data and model values
get_record Returns a record of model parameter values at the end of each iteration of the fitting process
get_flux | get_bflux Returns the unconvolved photon flux for source or background datasets
get_pflux2d Returns photon fluxes in 2-D images
get_eflux | get_beflux Returns the unconvolved energy flux for source or background datasets
get_eflux2d Returns energy fluxes in 2-D images
get_mcounts_sum | get_bmcounts_sum Returns the sum of convolved model counts in source and background datasets
get_mcounts_sum2d Returns sums of model counts in 2-D images
get_dcounts_sum | get_bdcounts_sum | get_net_counts_sum Returns the sum of observed counts in source and background datasets
get_dcounts_sum2d Returns sums of observed counts in 2-D images
get_eqwidth | get_beqwidth Returns the equivalent width of a line in source or background data
get_par Retrieve model parameter values, etc.
get_unc Retrieves parameter bounds
get_proj Retrieves parameter bounds
get_cov Retrieves parameter bounds
get_intunc Retrieves parameter value and best-fit statistic arrays
get_intproj Retrieves parameter value and best-fit statistic arrays
get_regunc Retrieves parameter value and best-fit statistic arrays
get_regproj Retrieves parameter value and best-fit statistic arrays
get_dimension Retrieve the dimensionality of source data
get_exptime | get_bexptime Retrieve source and background exposure times
get_backscale | get_bbackscale Retrieve source and background extraction region areas
get_qvalue Returns the statistical significance computed as a q-value
get_ftest Returns the statistical significance computed with the F test
get_lfactorial Returns the natural logarithm of the factorial of the input quantity
get_source_expr | get_bg_expr Get the source and background model stack expression
get_inst_expr | get_sinst_expr | get_binst_expr Get the source and background instrument model stack expression
get_filter_expr | get_bfilter_expr Retrieves description of filters applied to source and background datasets
get_method_expr Returns the name of the current optimization method
get_stat_expr Returns the name of the current statistic
get_defined_models | get_defined_inst_models Retrives lists of defined source and instrument models
get_models | get_inst_models Returns lists of available source and instrument models
get_model_params | get_inst_model_params Returns lists of parameter names for source and instrument models
get_num_par | get_num_par_frozen | get_num_par_thawed Reports the total number of parameters for all defined models, including instrument models
get_filename | get_bfilename | get_arf_filename | get_rmf_filename Retrieve filenames associated with a dataset
get_dir Returns the name of the current directory
get_verbose Returns Sherpa's verbosity

Bugs

See the Sherpa bug pages online for an up-to-date listing of known bugs.

Hardcopy (PDF): A4 | Letter
Last modified: December 2006



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