HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.

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freeze (and rfreeze)

set parameters as fixed

Do not allow indicated model parameters to vary. (See also thaw)

Syntax: freeze [<param range>...]

where <param range> ::= [<modelName>:]<param#>|<param#>- <param#>.

For response parameters (see gain command):

Syntax: rfreeze [<param range>...]

where <param range> ::= [<source number>:]<param#>|<param#>- <param#>.

The indicated model parameter or range of model parameters will be marked so they cannot be varied by the fit command. By default,the range will be the last range input by either a freeze or thaw command.

Examples:

Currently there are six parameters, initially all unfrozen. 

XSPEC12> freeze 2 
//Parameter 2 is frozen
XSPEC12> freeze 4-6
//Parameters 4, 5, and 6 are frozen.
XSPEC12> thaw 2 3-5
//Parameters 2, 4, and 5 are thawed, parameter 3 is unaffected.
XSPEC12> freeze 
//Parameters 3,4,5 are frozen (the last range input by a freeze 
//or thaw command).
XSPEC12> rfreeze 4-6
//Response parameters 4, 5, and 6 are frozen.

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Last modified: Friday, 23-Aug-2024 13:20:40 EDT

HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.