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Last modified: December 2010

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AHELP for CIAO 4.3 Sherpa v1


Context: modeling


Add parameters to a user-defined model


add_user_pars( modelname, parnames, [parvals, parmins, parmaxs,
parunits, parfrozen] )


The add_user_pars command sets up a user-defined model with parameter values which can be use in model definitions. Refer to the load_user_model help file for information on creating a model ("ahelp load_user_model") .

Note that all the parameters must be defined at the same time by add_user_pars. Each time the command is run, it overwrites any previously-defined parameters for the model.

  • modelname - the name of the model to which the parameters should be added
  • parnames - list of names for the new parameters ; default=None
  • parvals - list of parameter values; default=0
  • parmins - list of minimum values for the parameter ; default=-3.40282e+38
  • parmaxs - list of maximum values for the parameter ; default=3.40282e+38
  • parunits - list of parameter units; default=None
  • parfrozen - list of whether the parameters are frozen; default=False (the parameter is thawed)

The parameters must be specified in the order that the function expects. That is, if the function has two parameters, pars[0]=slope and pars[1]=y-intercept, then the call to "add_user_pars" must be ["slope", "yint"] (and not ["yint", "slope"]).

More information on creating custom models is available on the Sherpa website.

Example 1

sherpa> load_user_model( myline, "ml", )
sherpa> add_user_pars( ml, ["m","b"] )

Load a user model called "ml" and then add two parameters, "m" and "b". The default settings for the parameter values, units, etc. are used.

Example 2

sherpa> add_user_pars( custom, ["slope"], [30], parunits=["cm/s"],
parfrozen=[True] )

Add a parameter called "slope" to the model "custom". The initial parameter value is 30, the units are cm/s, and the parameter is frozen.


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, 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, load_user_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
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