Last modified: December 2020

URL: https://cxc.cfa.harvard.edu/sherpa/ahelp/load_table_model.html
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AHELP for CIAO 4.13 Sherpa v1

load_table_model

Context: modeling

Synopsis

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

Syntax

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

modelname - str
filename - str
method - func

Description

Note

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).


Examples

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 * (powlaw1d.pl + 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)

PARAMETERS

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.

Notes

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


Bugs

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

See Also

data
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
filtering
load_filter
info
get_default_id, list_bkg_ids, list_data_ids, list_model_ids, show_bkg_model, show_bkg_source
modeling
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
plotting
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
psfs
delete_psf, load_conv, load_psf
saving
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
statistics
load_user_stat
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