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Last modified: December 2013

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

set_exposure

Context: data

Synopsis

Set the exposure time

Syntax

set_exposure([id], exptime, [bkg_id])

Description

The set_exposure command sets the exposure time for the dataset. The specified exposure time replaces the current value of the exposure time, which may have been set from the value of the "EXPTIME" header keyword when the dataset was loaded.

  • id - the id of the dataset to use; if not given, uses the default dataset id (id=1 by default, see "ahelp get_default_id")
  • exptime - the exposure time [s]
  • bkg_id - the id of the background, if setting the background value; default=None

Example 1

sherpa> set_exposure(10e5)

Set the exposure time of the default dataset to 10e5 s.

Example 2

sherpa> set_exposure(2, 38500)

Set the exposure time for dataset id=2 to 38500 s.

Example 3

sherpa> set_exposure(1, 10e5, 1)

Set the exposure time for the first background of dataset id=1 to 10e5 s.

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_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_analysis, set_default_id
visualization
image_setregion

Last modified: December 2013
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