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Last modified: December 2013

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

set_analysis

Context: utilities

Synopsis

Set the units for spectral analysis

Syntax

set_analysis([id], quantity, [type,] [factor])

Description

The set_analysis command sets the units for spectral analysis. Note that in order to change the units of a data set from 'channel' to 'energy' or 'wavelength', the appropriate ARF and RMF instrument response files must be loaded.

  • id - the id of the dataset to use; default is to change the analysis setting for all datasets
  • quantity - the analysis setting: channel (or "chan" or "bin"), energy (or "ener"), wavelength (or "wave")
  • type - unit type for the y-axis of a plot: rate (the default) or counts
  • factor - integer indicating the number of times multiplied by energy (dE) or wavelength (dlambda). The default value is 0; values are listed below.

Values for the factor option

  • 0 = counts/sec/keV (the default)
  • 1 = counts/sec (with quantity="energy")
  • 2 = keV counts/sec (with quantity="energy")

Example 1

sherpa> set_analysis("wave")

Set the analysis quantity to wavelength for all datasets.

Example 2

sherpa> set_analysis(2, "chan")

Set the analysis quantity to channel for a dataset id=2.

Example 3

sherpa> set_analysis(1, "ener", "counts", 2)

Set the plot units for dataset id=1 to keV (x-axis) and counts*keV^2 (y-axis).

Bugs

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

See Also

confidence
set_conf_opt, set_covar_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_default_id
visualization
image_setregion

Last modified: December 2013
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