get_arf

sherpa.astro.ui.get_arf(id=None, resp_id=None, bkg_id=None)

Return the ARF associated with a PHA data set.

Parameters:
  • id (int or str, optional) – The data set to use. If not given then the default identifier is used, as returned by get_default_id.
  • resp_id (int or str, optional) – The identifier for the ARF within this data set, if there are multiple responses.
  • bkg_id (int or str, optional) – Set this to return the given background component.
Returns:

arf – This is a reference to the ARF, rather than a copy, so that changing the fields of the object will change the values in the data set.
Return type:

a sherpa.astro.instrument.ARF1D instance

See also

fake_pha()
Simulate a PHA data set from a model.
load_arf()
Load an ARF from a file and add it to a PHA data set.
load_pha()
Load a file as a PHA data set.
set_full_model()
Define the convolved model expression for a data set.
set_arf()
Set the ARF for use by a PHA data set.
set_rmf()
Set the RMF for use by a PHA data set.
unpack_arf()
Read in an ARF from a file.

Examples

Return the exposure field of the ARF from the default data set:

>>> get_arf().exposure

Copy the ARF from the default data set to data set 2:

>>> arf1 = get_arf()
>>> set_arf(2, arf1)

Retrieve the ARF associated to the second background component of the ‘core’ data set:

>>> bgarf = get_arf('core', 'bkg.arf', bkg_id=2)