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Last modified: December 2013

URL: http://cxc.harvard.edu/sherpa/ahelp/unpack_bkg.html
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AHELP for CIAO 4.9 Sherpa v1

unpack_bkg

Context: data

Synopsis

Unpack PHA data from a PHACrate

Syntax

unpack_bkg( filename|PHACrate, [use_errors=False] )

Description

The unpack_bkg command unpacks PHA data from a FITS file or a PHACrate into a Sherpa data object. unpack_bkg always returns a list of PHA datasets, in order to handle both Type I and II PHA files. To select specific elements after unpacking, use the syntax file[0], file[1], etc.

If a filename is provided as input, a crate is created but hidden and cannot be used for other analysis in the session.

  • filename|PHACrate - the name of the file (with path) or PHACrate which contains the PHA data
  • use_errors - read the statistical errors from the PHA file? default=False

Example 1

sherpa> bg1 = unpack_bkg("pha.fits")

Unpack the background spectrum into the object "bg1".

Example 2

sherpa> bgcr = read_pha("3c273.pha")
sherpa> bgdata = unpack_bkg(bgcr)

The spectrum is read into an PHACrate (named "bgcr") from the file 3c273.pha. The data is then unpacked into Sherpa from the crate.

Bugs

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

See Also

data
dataspace1d, dataspace2d, datastack, fake, fake_pha, load_arf, load_arrays, load_ascii, load_bkg, load_bkg_arf, load_bkg_rmf, load_data, load_grouping, load_image, load_multi_arfs, load_multi_rmfs, load_pha, load_quality, load_rmf, load_staterror, load_syserror, load_table, pack_image, pack_pha, pack_table, unpack_arf, unpack_arrays, unpack_ascii, unpack_data, unpack_image, unpack_pha, unpack_rmf, unpack_table
filtering
load_filter
info
get_default_id, list_bkg_ids, list_data_ids
modeling
add_model, add_user_pars, load_table_model, load_template_model, load_user_model, save_model, save_source
saving
save_arrays, save_data, save_delchi, save_error, save_filter, save_grouping, save_image, save_pha, save_quality, save_resid, save_staterror, save_syserror, save_table
statistics
load_user_stat

Last modified: December 2013
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