Create an ARF data structure.
Parameters: arg – Identify the ARF: a file name, or a data structure representing the data to use, as used by the I/O backend in use by Sherpa: a
TABLECratefor crates, as used by CIAO, or a list of AstroPy HDU objects.
Returns: arf Return type: a sherpa.astro.instrument.ARF1D instance
- Return the ARF associated with a PHA data set.
- Load an ARF from a file and add it to a PHA data set.
- Load an ARF from a file and add it to the background of a PHA data set.
- Load multiple ARFs for a PHA data set.
- Load a file as a PHA data set.
- Load a RMF from a file and add it to a PHA data set.
- Define the convolved model expression for a data set.
The minimum_energy setting of the ogip section of the Sherpa configuration file determines the behavior when an ARF with a minimum energy of 0 is read in. The default is to replace the 0 by the value 1e-10, which will also cause a warning message to be displayed.
>>> arf1 = unpack_arf("arf1.fits") >>> arf2 = unpack_arf("arf2.fits")
Read in an ARF using Crates:
>>> acr = pycrates.read_file("src.arf") >>> arf = unpack_arf(acr)
Read in an ARF using AstroPy:
>>> hdus = astropy.io.fits.open("src.arf") >>> arf = unpack_arf(hdus)