Last modified: December 2023

Jump to: Description · Examples · PARAMETERS · Notes · Bugs · See Also

AHELP for CIAO 4.16 Sherpa


Context: modeling


Load tabular or image data and use it as a model component.


load_table_model(modelname, filename, method=linear_interp, *args,

modelname - str
filename - str
method - func



Deprecated in Sherpa 4.9 The new `load_xstable_model` routine should be used for loading XSPEC table model files. Support for these files will be removed from `load_table_model` in the next release.

A table model is defined on a grid of points which is interpolated onto the independent axis of the data set. The model will have at least one parameter (the amplitude, or scaling factor to multiply the data by), but may have more (if X-Spec table models are used).


Example 1

Load in the data from filt.fits and use it to multiply the source model (a power law and a gaussian). Allow the amplitude for the table model to vary between 1 and 1e6, starting at 1e3.

>>> load_table_model('filt', 'filt.fits')
>>> set_source(filt * ( + gauss1d.gline))
>>> set_par(filt.ampl, 1e3, min=1, max=1e6)

Example 2

Load in an image ("broad.img") and use the pixel values as a model component for data set "img":

>>> load_table_model('emap', 'broad.img')
>>> set_source('img', emap * gauss2d)


The parameters for this function are:

Parameter Definition
modelname The identifier for this table model.
filename The name of the file containing the data, which should contain two columns, which are the x and y values for the data, or be an image.
method The interpolation method to use to map the input data onto the coordinate grid of the data set. Linear, nearest-neighbor, and polynomial schemes are provided in the sherpa.utils module.
args Arguments for reading in the data.
kwargs Keyword arguments for reading in the data.


Examples of interpolation schemes provided by `sherpa.utils` are: `linear_interp` , `nearest_interp` , `neville` , and `neville2d` .


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_chisqr_plot, get_bkg_delchi_plot, get_bkg_fit_plot, get_bkg_model_plot, get_bkg_plot, get_bkg_ratio_plot, get_bkg_resid_plot, get_bkg_source_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_num_par_frozen, get_num_par_thawed, get_order_plot, get_par, get_pileup_model, get_source, get_source_component_image, get_source_component_plot, get_source_contour, get_source_image, get_source_plot, get_xsabund, get_xscosmo, get_xsxsect, get_xsxset, image_model, image_model_component, image_source, image_source_component, integrate, link, load_template_interpolator, load_template_model, load_user_model, load_xstable_model, normal_sample, reset, save_model, save_source, set_bkg_model, set_bkg_source, set_full_model, set_model, set_model_autoassign_func, set_pileup_model, set_source, set_xsabund, set_xscosmo, set_xsxsect, set_xsxset, t_sample, uniform_sample
get_cdf_plot, get_pdf_plot, 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, load_psf
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