| AHELP for CIAO 4.5 Sherpa v1 | freeze |
Context: modeling |
Synopsis
Freeze model parameters, so they do not vary during a fit.
Syntax
freeze([parameter], [[parameters]])
Description
Given one or more model parameters, freeze each model parameter at its current value. The frozen parameters are not varied during a fit. (If an argument is a model, then all the model parameters of that model are frozen.)
- parameter(s) - model parameters to freeze for the fit
One of more model parameters may be specified as a comma-separated list. If the model name is provided without a parameter specified, all of the parameters in the model are frozen.
To unfreeze model parameter values and allow them to vary, the command thaw ("ahelp thaw") is used.
Example 1
sherpa> freeze(g.ampl)
The model parameter "ampl" of model "g" is frozen at its current value.
Example 2
sherpa> freeze(g.ampl, g.fwhm)
Both model parameters "ampl" and "fwhm" of model "g" are frozen at their current values.
Example 3
sherpa> freeze(g)
All model parameters specified in model "g" are frozen at their current values.
Bugs
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.

![[Sherpa Logo]](../imgs/sherpa_logo_navbar.gif)