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Last modified: December 2013

URL: http://cxc.harvard.edu/sherpa/ahelp/create_model_component.html
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AHELP for CIAO 4.6 Sherpa v1

create_model_component

Context: modeling

Synopsis

Create a new model component

Syntax

create_model_component( typename, name )

Description

The create_model_component command is an explicit means of setting and naming a model by type. It is called implicitly when the set_source command ("ahelp set_source") is used. The model is created with parameters set to the default values.

  • typename - the type of model to establish; see "ahelp models" for a list of options
  • name - the name for the model. Once assigned, it is in the local variable scope.

This command is equivalent to "typename.name" when using the default model automatic assignment function; see "ahelp set_model_autoassign_func" for more information.

Example 1

sherpa> create_model_component("powlaw1d", "p1")
sherpa> list_model_components()
['p1']

Create an instance of a 1D powerlaw model named "p1". The model is established with the default settings:

sherpa> print(p1)
powlaw1d.p1
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   p1.gamma     thawed            1          -10           10
   p1.ref       frozen            1     -3.4e+38      3.4e+38
   p1.ampl      thawed            1            0      3.4e+38

Example 2

sherpa> create_model_component("bbody", "bb")
sherpa> list_model_components()
['bb']

Establish a blackbody model named "bb" with the default settings:

sherpa> print(bb)
bbody.bb
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   bb.space     thawed            0            0            1 0 - energy | 1 - wave
   bb.kT        thawed            1          0.1        1e+03        keV
   bb.ampl      thawed            1        1e-20        1e+20

sherpa> print(bb.ampl)
val     = 1
min     = 1e-20
default = 1
max     = 1e+20
units   =
frozen  = False
link    = None

Bugs

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

See Also

data
get_bkg_plot
info
list_model_ids, show_bkg_model, show_bkg_source
modeling
add_model, add_user_pars, clean, 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
plotting
get_lrt_plot, get_lrt_results, get_pvalue_plot, get_pvalue_results, plot_cdf, plot_lrt, plot_model, plot_model_component, plot_pdf, plot_pvalue, plot_scatter, plot_source, plot_source_component, plot_trace
psfs
delete_psf, load_conv
saving
save_delchi, save_resid
utilities
calc_chisqr, calc_energy_flux, calc_model_sum, calc_photon_flux, calc_source_sum, calc_stat, eqwidth
visualization
contour_model, contour_ratio, contour_resid, get_ratio, get_resid

Last modified: December 2013
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