get_fit_results

Context: fitting

Synopsis

Return the results of the last fit.

Syntax

get_fit_results()

Description

This function returns the results from the most-recent fit. The returned value includes information on the parameter values and fit statistic.

Examples

Example 1

Display the fit results:

>>> print(get_fit_results())

Example 2

Inspect the fit results:

>>> res = get_fit_results()
>>> res.statval
498.21750663761935
>>> res.dof
439
>>> res.parnames
('pl.gamma', 'pl.ampl', 'gline.fwhm', 'gline.pos', 'gline.ampl')
>>> res.parvals
(-0.20659543380329071, 0.00030398852609788524, 100.0, 4900.0, 0.001)

PARAMETERS

This function has no parameters

Return value

The return value from this function is:

stats -- The results of the last fit. It does not reflect any changes made to the model parameter, or settings, since the last fit.

Notes

The fields of the object include:

Item	Definition
datasets	A sequence of the data set ids included in the results.
itermethodname	What iterated-fit scheme was used, if any (as set by `set_iter_method` ).
statname	The name of the statistic function (as used in `set_stat` ).
succeeded	Was the fit successful (did it converge)?
parnames	A tuple of the parameter names that were varied in the fit (the thawed parameters in the model expression).
parvals	A tuple of the parameter values, in the same order as parnames .
statval	The statistic value after the fit.
istatval	The statistic value at the start of the fit.
dstatval	The change in the statistic value ( istatval - statval ).
numpoints	The number of bins used in the fits.
dof	The number of degrees of freedom in the fit (the number of bins minus the number of free parameters).
qval	The Q-value (probability) that one would observe the reduced statistic value, or a larger value, if the assumed model is true and the current model parameters are the true parameter values. This will be none if the value can not be calculated with the current statistic (e.g. the Cash statistic).
rstat	The reduced statistic value (the statval field divided by dof ). This is not calculated for all statistics.
message	A message about the results of the fit (e.g. if the fit was unable to converge). The format and contents depend on the optimisation method.
nfev	The number of model evaluations made during the fit.

Bugs

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