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Last modified: December 2013

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AHELP for CIAO 4.9 Sherpa v1


Context: modeling


Add a user-defined model class as a Sherpa model type




The add_model command registers a user-defined Sherpa model class as a Sherpa model type, to allow users to create instances of models that are recognized automatically in Sherpa model expressions. This is primarily an alternative to using load_user_model and the add_user_pars commands for explicitly defining user models as Python classes for use in Sherpa.

  • modelclass - a Python class that characterizes a user-defined Sherpa model class type.

Example 1

sherpa> from sherpa.models import Gauss1D
sherpa> class MyGauss1D(Gauss1D): pass
sherpa> add_model(MyGauss1D)
sherpa> set_source(mygauss1d.g1 + mygauss1d.g2)

Define a Python class, MyGauss1D, that inherits from the Sherpa Gauss1D model class. Register MyGauss1D as a Sherpa model type for use in Sherpa model expressions using add_model().

Example 2

sherpa> from sherpa.models import PowLaw1D
sherpa> class MyPowLaw1D(PowLaw1D): pass
sherpa> add_model(MyPowLaw1D)
sherpa> set_source(xswabs.abs1 * mypowlaw1d.p1)

Define a Python class, MyPowLaw1D, that inherits from the Sherpa Powlaw1D model class. Register MyPowLaw1D as a Sherpa model type for use in Sherpa model expressions using add_model(). Set the model expression for data set 1 to an absorbed power law, using the newly defined model type.


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

See Also

dataspace1d, dataspace2d, datastack, 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_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, integrate1d, link, load_table_model, load_template_model, load_user_model, normal_sample, 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, t_sample, uniform_sample
get_lrt_plot, get_lrt_results, get_pvalue_plot, get_pvalue_results, plot_cdf, plot_model, plot_model_component, plot_pdf, plot_pvalue, plot_scatter, plot_source, plot_source_component, plot_trace
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 2013
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