Synopsis
Calculate the per-bin chi-squared statistic.
Syntax
calc_chisqr(id=None, *otherids)
Description
Evaluate the model for one or more data sets, compare it to the data using the current statistic, and return an array of chi-squared values for each bin. No fitting is done, as the current model parameter, and any filters, are used.
Examples
Example 1
When called with no arguments, the return value is the chi-squared statistic for each bin in the data sets which have a defined model.
>>> calc_chisqr()
Example 2
Supplying a specific data set ID to calc_chisqr - such as "1" or "src" - will return the chi-squared statistic array for only that data set.
>>> calc_chisqr(1)
>>> calc_chisqr("src")Example 3
Restrict the calculation to just datasets 1 and 3:
>>> calc_chisqr(1, 3)
PARAMETERS
The parameters for this function are:
| Parameter | Type information | Definition |
|---|---|---|
| id | int, str, or None, optional | The data set that provides the data. If not given then all data sets with an associated model are used simultaneously. |
| *otherids | int or str, optional | Other data sets to use in the calculation. |
Return value
The return value from this function is:
chisq -- The chi-square value for each bin of the data, using the current statistic (as set by `set_stat` ). A value of none is returned if the statistic is not a chi-square distribution.
Notes
The output array length equals the sum of the arrays lengths of the requested data sets.
Bugs
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.
See Also
- data
- 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
- fitting
- fit, simulfit
- info
- list_model_ids, show_bkg_model, show_bkg_source
- methods
- get_iter_method_name, get_iter_method_opt, list_iter_methods, set_iter_method, set_iter_method_opt
- 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, image_model, image_model_component, image_source, image_source_component, integrate, link, load_table_model, load_template_interpolator, load_template_model, load_user_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, t_sample, uniform_sample
- plotting
- get_cdf_plot, get_pdf_plot, get_pvalue_plot, get_pvalue_results, plot_cdf, plot_fit, plot_fit_delchi, plot_fit_resid, 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
- statistics
- get_stat, get_stat_name
- tools::response
- color_color, modelflux
- tools::statistics
- aprates
- utilities
- calc_energy_flux, calc_model_sum, calc_photon_flux, calc_source_sum, calc_stat, eqwidth, gamma, igam, igamc, incbet, lgam
- visualization
- contour_model, contour_ratio, contour_resid, image_fit