# get_exposure¶

sherpa.astro.ui.get_exposure(id=None, bkg_id=None)

Return the exposure time of a PHA data set.

The exposure time of a PHA data set is taken from the EXPTIME keyword in its header, but it can be changed once the file has been loaded.

Parameters: id (int or str, optional) – The identifier for the data set to use. If not given then the default identifier is used, as returned by get_default_id. bkg_id (int or str, optional) – Set to identify which background component to use. The default value (None) means that the time is for the source component of the data set. exposure – The exposure time, in seconds. number

get_areascal()
Return the fractional area factor of a PHA data set.
get_backscal()
Return the area scaling of a PHA data set.
set_exposure()
Change the exposure time of a PHA data set.

Examples

Return the exposure time for the default data set.

>>> t = get_exposure()


Return the exposure time for the data set with identifier 2:

>>> t2 = get_exposure(2)


Return the exposure time for the first background component of data set “core”:

>>> tbkg = get_exposure('core', bkg_id=1)