get_areascal

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

Return the fractional area factor of a PHA data set.

Return the AREASCAL setting [1] for the source or background component of a PHA data set.

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 value is for the source component of the data set.
Returns:

areascal – The AREASCAL value, which can be a scalar or a 1D array.

Return type:

number or ndarray

See also

get_backscal()
Return the area scaling of a PHA data set.
set_areascal()
Change the fractional area factor of a PHA data set.

Notes

The fractional area scale is normally set to 1, with the ARF used to scale the model.

References

[1]“The OGIP Spectral File Format”, Arnaud, K. & George, I. http://heasarc.gsfc.nasa.gov/docs/heasarc/ofwg/docs/spectra/ogip_92_007/ogip_92_007.html

Examples

Return the AREASCAL value for the default data set:

>>> get_areascal()

Return the AREASCAL value for the first background component of dataset 2:

>>> get_areascal(id=2, bkg_id=1)