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Last modified: December 2013

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

unsubtract

Context: data

Synopsis

Undo background subtraction

Syntax

unsubtract( id )

Description

The unsubtract command undoes the background subtraction to restore the input source dataset amplitudes.

  • id - the id of the dataset to unsubtract; if not given, uses the default dataset id (id=1 by default, see "ahelp get_default_id")

The "subtracted" field of the source dataset is updated to indicate that the data are not background-subtracted, as shown in the examples.

To background-subtract a dataset, use the subtract command ("ahelp subtract").

Example 1

sherpa> unsubtract()

Undo the background subtraction of the default dataset.

Example 2

sherpa> unsubtract("src")
sherpa> get_data("src").subtracted
False

Undo the background subtraction of the dataset "src". The "subtracted" field of the source data object is updated to show that the dataset is not background-subtracted.

Bugs

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

See Also

data
get_bkg, set_bkg, subtract
info
list_bkg_ids, show_bkg_model, show_bkg_source
modeling
delete_bkg_model
plotting
plot_bkg

Last modified: December 2013
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