Synopsis
Return the results of the last covar run.
Syntax
get_covar_results()
Description
The function is also called get_covariance_results().
Examples
Example 1
>>> res = get_covar_results()
>>> print(res)
datasets = (1,)
methodname = covariance
iterfitname = none
fitname = levmar
statname = chi2gehrels
sigma = 1
percent = 68.2689492137
parnames = ('bgnd.c0',)
parvals = (10.228675427602724,)
parmins = (-2.4896739438296795,)
parmaxes = (2.4896739438296795,)
nfits = 0Example 2
In this case, of a single parameter, the covariance matrix is just the variance of the parameter:
>>> res.extra_output array([[ 6.19847635]])
Notes
The fields of the object include:
| Item | Definition |
|---|---|
| datasets | A tuple of the data sets used in the analysis. |
| methodname | This will be 'covariance'. |
| iterfitname | The name of the iterated-fit method used, if any. |
| fitname | The name of the optimization method used. |
| statname | The name of the fit statistic used. |
| sigma | The sigma value used to calculate the confidence intervals. |
| percent | The percentage of the signal contained within the confidence intervals (calculated from the sigma value assuming a normal distribution). |
| parnames | A tuple of the parameter names included in the analysis. |
| parvals | A tuple of the best-fit parameter values, in the same order as parnames . |
| parmins | A tuple of the lower error bounds, in the same order as parnames . |
| parmaxes | A tuple of the upper error bounds, in the same order as parnames . |
| nfits | The number of model evaluations. |
There is also an extra_output field which is used to return the covariance matrix.
Bugs
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.
See Also
- confidence
- conf, confidence, covar, covariance, get_conf, get_conf_results, get_covar, get_covar_opt, get_covariance_results, get_int_proj, get_int_unc, get_proj, get_proj_opt, get_proj_results, get_projection_results, get_reg_proj, get_reg_unc, int_proj, int_unc, proj, projection, reg_proj, reg_unc, set_conf_opt, set_covar_opt, set_proj_opt
- contrib
- get_chart_spectrum, get_marx_spectrum
- data
- get_areascal, get_arf, get_arf_plot, get_axes, get_backscal, get_bkg, get_bkg_arf, get_bkg_chisqr_plot, get_bkg_delchi_plot, get_bkg_fit_plot, get_bkg_model, get_bkg_model_plot, get_bkg_plot, get_bkg_ratio_plot, get_bkg_resid_plot, get_bkg_rmf, get_bkg_scale, get_bkg_source, get_bkg_source_plot, get_coord, get_counts, get_data, get_data_contour, get_data_contour_prefs, get_data_image, get_data_plot, get_data_plot_prefs, get_dep, get_dims, get_error, get_exposure, get_grouping, get_indep, get_quality, get_rmf, get_specresp, get_staterror, get_syserror
- filtering
- get_filter
- fitting
- calc_stat_info, get_stat_info
- info
- get_default_id, list_stats
- methods
- get_draws, get_iter_method_name, get_iter_method_opt, get_method, get_method_name, get_method_opt
- modeling
- get_model, 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_response, get_source, get_source_component_image, get_source_component_plot, get_source_contour, get_source_image, get_source_plot, image_source
- plotting
- get_split_plot
- psfs
- get_psf, get_psf_contour, get_psf_image, get_psf_plot
- statistics
- get_chisqr_plot, get_delchi_plot, get_prior, get_sampler, get_stat, get_stat_name
- utilities
- get_analysis, get_rate
- visualization
- image_getregion