unpack_bkg

Context: data

Synopsis

Create a PHA data structure for a background data set.

Syntax

unpack_bkg(arg, use_errors=False)

use_errors - bool, optional

Description

Any instrument information referenced in the header of the PHA file - e.g. with the ANCRFILE and RESPFILE, keywords - will also be loaded. Unlike `unpack_pha` , background files will not be loaded.

Examples

Example 1

>>> pha1 = unpack_arf("src1.pi")
>>> pha2 = unpack_bkg("field.pi")
>>> set_data(1, pha1)
>>> set_bkg(1, pha2)

Example 2

Read in a PHA file using Crates:

>>> cr = pycrates.read_file("bg.fits")
>>> pha = unpack_pha(cr)

Example 3

Read in a PHA file using AstroPy:

>>> hdus = astropy.io.fits.open("bg.fits")
>>> pha = unpack_pha(hdus)

PARAMETERS

The parameters for this function are:

Parameter	Definition
arg	Identify the PHA file: a file name, or a data structure representing the data to use, as used by the I/O backend in use by Sherpa: a tablecrate for crates, as used by CIAO, or a list of AstroPy HDU objects.
use_errors	If True then the statistical errors are taken from the input data, rather than calculated by Sherpa from the count values. The default is False .

Bugs

See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.