Chandra X-Ray Observatory
Skip to the navigation links
Last modified: December 2010

Jump to: Description · Examples · Bugs · See Also

AHELP for CIAO 4.3 Sherpa v1


Context: modeling


Load a user-defined model


load_user_model( func, modelname, [filename])


The load_user_model command creates a user-defined model from a function that has been defined previously in Sherpa or is supplied in a file. The add_user_pars function can then be used to establish model parameters ("ahelp add_user_pars"). .

  • func - the function which should be used to create the model
  • modelname - a name for the new model
  • filename - (optional) the name of a file, including path, which contains the function ("func").

If the function is being loaded from a file, some additional options are allowed. A table will accept the arguments to load_table: ncols, colkeys, dstype ("ahelp load_table"). An image will accept the argument associated with load_image: coord ("ahelp load_image").

An alternative to using load_user_model together with add_user_pars is the add_model function, which explicitly defines user models as Python classes for use in Sherpa (see "ahelp add_model").

Example 1

sherpa> load_user_model( myline, "ml", )

Create a model named "ml" from the function "myline", which has been previously defined in Sherpa.

Example 2

sherpa> load_user_model( custom, "mymod", "model_file.fits" )

Create a model named "mymod" from the function "custom" which is defined in model_file.fits.

Example 3

sherpa> load_user_model( myline, "ml", "myline.fits[cols SUR_BRI]" )
sherpa> load_user_model( myline, "ml", "myline.fits", ncols=1)

Two similar methods of creating a model named "ml" from the function "myline" in myline.fits. The first method specifies which column in the file should be read, while the second simply indicates that the first column should be used.


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

See Also

dataspace1d, dataspace2d, fake, get_bkg_plot, 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_bkg, unpack_data, unpack_image, unpack_pha, unpack_rmf, unpack_table
get_default_id, list_bkg_ids, list_data_ids, list_model_ids, show_bkg_model, show_bkg_source
add_model, add_user_pars, clean, create_model_component, delete_bkg_model, delete_model, delete_model_component, get_model, get_model_autoassign_func, get_model_component, get_model_component_image, get_model_component_plot, get_model_plot, get_num_par, get_order_plot, get_par, get_pileup_model, get_source, get_source_component_image, get_source_component_plot, image_model, image_model_component, image_source, image_source_component, integrate, link, load_table_model, reset, save_model, save_source, set_bkg_model, set_full_model, set_model_autoassign_func, set_pileup_model, set_source, set_xsabund, set_xscosmo, set_xsxsect, set_xsxset
plot_model, plot_model_component, plot_source, plot_source_component
delete_psf, load_conv
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
calc_chisqr, calc_energy_flux, calc_model_sum, calc_photon_flux, calc_source_sum, calc_stat, eqwidth
contour_model, contour_ratio, contour_resid, get_ratio, get_resid

Last modified: December 2010
Smithsonian Institute Smithsonian Institute

The Chandra X-Ray Center (CXC) is operated for NASA by the Smithsonian Astrophysical Observatory. 60 Garden Street, Cambridge, MA 02138 USA.   Email: Smithsonian Institution, Copyright © 1998-2019. All rights reserved.