Following the F B command are GICO commands, in
which the fit variables
have to appear. At the position where the variables that are to be fitted
can be computed, the command:
2 F(IT) V(ARIABLES) <list of fit variables> ;
[example: F V F1 F2 ;]
must be inserted. Note that there is a difference between naming only one
or several variables; in each case, different routines are used internally.
The command:
3 F(IT) E(ND)<tolerance> <max. Iterations>
<fit routine> ;
[example: F E 1.E-5 150 1 ;]
[default: F E 1.E-4 100 1 ;]
ends the fit. The
value for the fit routine for a single fit variable may be between 1 and 6.
If more than one variable is to be fitted, the value of the fit routine
must be 1, which is the default.
GICO tries to change the variables in a way that the fit variables become
0. The success of the fit depends on the chosen fit variable, the fit
routine, the tolerance and the starting values for the variables.
The results of the fit can be looked up in the GICO output. They are
also written in a more compact form onto the file GICOFIT.DAT.
Sometimes it may be desirable to disable a fit for one calculation.
This can be done by commenting out the Fit Begin, Fit Variables and
Fit End commands. A quicker way is to use the command:
2 F(IT) D(ISABLE) ;
[example: F D ;]
which may appear between a Fit Begin and Fit End and will prevent this
fit from being executed.