Synopsis
Allow model parameters to be varied during a fit.
Syntax
thaw(*args) args - sequence of str or Parameter or Model
Description
The arguments can be parameters or models, in which case all parameters of the model are thawed. If no arguments are given then nothing is changed.
Examples
Example 1
Ensure that the FWHM parameter of the line model (in this case a `gauss1d` model) will be varied in any fit.
>>> set_source(const1d.bgnd + gauss1d.line) >>> thaw(line.fwhm) >>> fit()
Example 2
Thaw all parameters of the line model and then re-fit:
>>> thaw(line) >>> fit()
Example 3
Thaw the nh parameter of the gal model and the abund parameter of the src model:
>>> thaw(gal.nh, src.abund)
PARAMETERS
The parameter for this function is:
| Parameter | Definition |
|---|---|
| args | The parameters or models to thaw. |
Notes
The `freeze` function can be used to reverse this setting, so that parameters are "frozen" and so remain constant during a fit.
Certain parameters may be marked as "always frozen", in which case using the parameter in a call to `thaw` will raise an error. If the model is sent to `thaw` then the "always frozen" parameter will be skipped.
Bugs
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.