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Last modified: December 2013

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AHELP for CIAO 4.9 Sherpa v1


Context: data


Unpack PHA data from a PHACrate


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


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.


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

See Also

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
get_default_id, list_bkg_ids, list_data_ids
add_model, add_user_pars, load_table_model, load_template_model, load_user_model, save_model, save_source
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

Last modified: December 2013
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