- sherpa.astro.ui.load_bkg(id, arg=None, use_errors=False, bkg_id=None)
Load the background from a file and add it to a PHA data set.
This will load the PHA data and any response information - so ARF and RMF - and add it as a background component to the PHA data set.
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
arg – Identify the data to read: a file name, or a data structure representing the data to use, as used by the I/O backend in use by Sherpa: a
PHACrateDatasetfor crates, as used by CIAO, or a list of AstroPy HDU objects.
use_errors (bool, optional) – If
Truethen the statistical errors are taken from the input data, rather than calculated by Sherpa from the count values. The default is
bkg_id (int or str, optional) – The identifier for the background (the default of
Noneuses the first component).
Load an ARF from a file and add it to the background of a PHA data set.
Load a RMF from a file and add it to the background of a PHA data set.
Load a PHA data set.
The function does not follow the normal Python standards for parameter use, since it is designed for easy interactive use. When called with a single un-named argument, it is taken to be the
argparameter. If given two un-named arguments, then they are interpreted as the
argparameters, respectively. The remaining parameters are expected to be given as named arguments.
Load a source and background data set:
>>> load_pha('src.pi') read ARF file src.arf read RMF file src.rmf >>> load_bkg('src_bkg.pi')
Read in the background via Crates:
>>> bpha = pycrates.read_pha('src_bkg.pi') >>> load_bkg(bpha)
Create the data set from the data read in by AstroPy:
>>> bhdus = astropy.io.fits.open('src_bkg.pi') >>> load_bkg(bhdus)