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Last modified: December 2013

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

save_grouping

Context: saving

Synopsis

Save grouping flags to a FITS table or ASCII file

Syntax

save_grouping( [id=1], filename, [bkg_id=1,ascii=False,clobber=False] )

Description

The save_grouping command saves the array of grouping flags associated with a data set to a column in a FITS table file or column-based ASCII file, by data set id. An array element set to 1 marks the beginning of a group and an element set to -1 marks subsequent members of that group.

  • id - the id of the data set to which the group array has been assigned; if not given, uses the default data set id (id=1 by default, see "ahelp get_default_id")
  • filename - name of outfile
  • bkd_id - the id of the background data set to use (e.g., bkg_id=1 represents the first background data set loaded in association with the source data set specified in the 'id' argument)
  • ascii - outfile format specification; True to save outfile in ASCII format, False for FITS, default=False
  • clobber - clobber outfile; default=False (do not clobber if file exists)

Example 1

sherpa> save_grouping("group.fits")

The save_grouping function can be called with just a filename, in which case all the default arguments will be used. In this example, the grouping scheme associated with data set id=1 is written to the FITS table file 'group.fits'.

ciao% dmlist group.fits blocks
--------------------------------------------------------------------------------
Dataset: group.fits
--------------------------------------------------------------------------------
 
     Block Name                          Type         Dimensions
--------------------------------------------------------------------------------
Block    1: PRIMARY                        Null        
Block    2: TABLE                          Table         2 cols x 8192     rows
	ciao% dmlist group.fits data
--------------------------------------------------------------------------------
Data for Table Block TABLE
--------------------------------------------------------------------------------
 
ROW    CHANNEL              GROUPS
 
     1                  1.0          1
     2                  2.0         -1
     3                  3.0         -1
     4                  4.0         -1
     5                  5.0         -1
     6                  6.0         -1
     7                  7.0          1
     8                  8.0         -1
     9                  9.0         -1
     .
     .
     .
[rest of output omitted] 

Example 2

sherpa> save_grouping(2, "group.txt", ascii=True)

Here, the optional 'ascii' argument is set to True in order to produce an outfile in ASCII format (overriding the default setting ascii=False). The grouping scheme assigned to data set id=2 is written to the text file 'group.txt'.

Example 3

sherpa> save_grouping(2,"group_bkg.fits", bkg_id=1, clobber=True)

The group array associated with the first background data set loaded for source data set 2 is written to FITS file group_bkg.fits (note the 'ascii' parameter default is False).

See Also

contrib
save_chart_spectrum
data
copy_data, dataspace1d, dataspace2d, datastack, delete_data, fake, get_axes, get_bkg_plot, get_counts, get_data, get_data_plot, get_dep, get_dims, get_error, get_grouping, get_quality, get_specresp, get_staterror, get_syserror, group, 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, set_data, set_grouping, set_quality, ungroup, unpack_arf, unpack_arrays, unpack_ascii, unpack_bkg, unpack_data, unpack_image, unpack_pha, unpack_rmf, unpack_table
filtering
get_filter, load_filter, set_filter
info
get_default_id, list_bkg_ids, list_data_ids, list_response_ids
modeling
add_model, add_user_pars, clean, load_table_model, load_template_model, load_user_model, save_model, save_source
plotting
plot_data, set_xlinear, set_xlog, set_ylinear, set_ylog
saving
restore, save, save_all, save_arrays, save_data, save_delchi, save_error, save_filter, save_image, save_pha, save_quality, save_resid, save_staterror, save_syserror, save_table, script
statistics
load_user_stat
utilities
calc_data_sum, calc_data_sum2d, calc_ftest, calc_kcorr, calc_mlr, calc_model_sum2d, calc_source_sum2d, get_rate
visualization
contour, contour_data, contour_ratio, get_ratio, get_resid, histogram1d, histogram2d, image_data, rebin

Last modified: December 2013
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