Synopsis
Return the data used by plot_pvalue.
Syntax
get_pvalue_plot(null_model=None, alt_model=None, conv_model=None, id=1, otherids=(), num=500, bins=25, numcores=None, recalc=False)
Description
Access the data arrays and preferences defining the histogram plot produced by the `plot_pvalue` function, a histogram of the likelihood ratios comparing fits of the null model to fits of the alternative model using faked data with Poisson noise. Data returned includes the likelihood ratio computed using the observed data, and the p-value, used to reject or accept the null model.
Examples
Example 1
Return the values from the last call to `plot_pvalue` :
>>> pvals = get_pvalue_plot() >>> pvals.ppp 0.472
Example 2
Run 500 simulations for the two models and print the results:
>>> pvals = get_pvalue_plot(mdl1, mdl2, recalc=True, num=500) >>> print(pvals)
PARAMETERS
The parameters for this function are:
| Parameter | Type information | Definition |
|---|---|---|
| null_model | The model expression for the null hypothesis. | |
| alt_model | The model expression for the alternative hypothesis. | |
| conv_model | optional | An expression used to modify the model so that it can be compared to the data (e.g. a PSF or PHA response). |
| id | int or str, optional | The data set that provides the data. The default is 1. |
| otherids | sequence of int or str, optional | Other data sets to use in the calculation. |
| num | int, optional | The number of simulations to run. The default is 500. |
| bins | int, optional | The number of bins to use to create the histogram. The default is 25. |
| numcores | optional | The number of CPU cores to use. The default is to use all the cores on the machine. |
| recalc | bool, optional | The default value ( False ) means that the results from the last call to `plot_pvalue` or `get_pvalue_plot` are returned. If True , the values are re-calculated. |
Notes
The `set_rng` routine is used to control how the random numbers are generated.
Changes in CIAO
Changed in CIAO 4.17
The "wstat" statistic can now be used with this routine.
Bugs
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.
See Also
- contrib
- get_data_prof, get_data_prof_prefs, get_delchi_prof, get_delchi_prof_prefs, get_fit_prof, get_model_prof, get_model_prof_prefs, get_resid_prof, get_resid_prof_prefs, get_source_prof, get_source_prof_prefs, plot_chart_spectrum, plot_marx_spectrum, prof_data, prof_delchi, prof_fit, prof_fit_delchi, prof_fit_resid, prof_model, prof_resid, prof_source
- data
- get_arf_plot, 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
- info
- 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, 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_energy_flux_hist, get_pdf_plot, get_photon_flux_hist, get_pvalue_results, get_split_plot, plot, plot_arf, plot_bkg, plot_bkg_chisqr, plot_bkg_delchi, plot_bkg_fit, plot_bkg_fit_delchi, plot_bkg_fit_resid, plot_bkg_model, plot_bkg_ratio, plot_bkg_resid, plot_bkg_source, plot_cdf, plot_chisqr, plot_data, plot_delchi, plot_energy_flux, plot_fit, plot_fit_delchi, plot_fit_resid, plot_model, plot_model_component, plot_order, plot_pdf, plot_photon_flux, plot_pvalue, plot_ratio, plot_resid, plot_scatter, plot_source, plot_source_component, plot_trace, set_xlinear, set_xlog, set_ylinear, set_ylog
- psfs
- delete_psf, load_conv, plot_kernel
- saving
- save_delchi, save_resid
- statistics
- get_chisqr_plot, get_delchi_plot
- 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