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Last modified: December 2013

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AHELP for CIAO 4.10 Sherpa v1


Context: modeling


Thaw model parameters so they vary during a fit




The thaw command thaws the specified model parameters so that they may vary during a fit.

  • parameter(s) - parameters to thaw

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 thawed.

To fix a parameter at the current value during a fit, use the freeze command ("ahelp freeze").


Example 1

sherpa> thaw(pl.ampl)

Thaw the amplitude parameter of a powerlaw1d model named "pl".

Example 2

sherpa> set_source(*xsmekal.mek)
sherpa> thaw(mek.kT)

Create a source model and thaw the plasma temperature parameter (kt) of the xsmekal model.

Example 3

sherpa> thaw(poly.c1, poly.c2)

Thaw the second and third (c1, c2) coefficients of a polynomial model.

Example 4

sherpa> thaw(poly)

Thaw all of the components of the polynomial model.


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

See Also

freeze, guess, link, paramprompt, set_par, unlink

Last modified: December 2013
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