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Last modified: December 2013

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

get_areascal

Context: data

Synopsis

Return the source or background pixel fractional area scale

Syntax

get_areascal( [id, bkg_id] )

Description

The get_areascal() function returns the pixel area scaling factor for a source or background data set by data set ID or background ID. The fractional area scale is normally set to "1" pixel in spectral analysis, and the ARF is used to scale the data. The set_areascal() function may be used to change the fractional area scale of a source or background data set.

  • id - the id of the data set to use; if not given, uses the default dataset id (id=1 by default, see "ahelp get_default_id")
  • bkg_id - the id of the background to use

Example 1

sherpa> get_areascal()

When called with no arguments, get_areascal() returns the pixel fractional area of the source in the default data set.

sherpa> get_areascal()
1.0

Example 2

sherpa> get_areascal(id=2, bkg_id=1)

To return the fractional area scale for a background associated with a source data set, the data set ID and background ID must be supplied to get_areascal().

sherpa> get_areascal(2, 1)
1.0
sherpa> get_areascal(2, 1);
1.0

Bugs

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

See Also

confidence
get_conf, get_covar, get_int_proj, get_int_unc, get_proj, get_reg_proj, get_reg_unc
contrib
get_chart_spectrum
data
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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