Institut für Astronomie und AstrophysikAbteilung AstronomieSand 1, D-72076 Tübingen, Germany |
minimize
Tries to minimize a specific metric (e.g. chi^2) by changing model parameters.
cafe
minimize, metric [,iterations][,/selected][,/quiet]
metric - The operator which maps the data/model to an value which is to be minimized. iterations - (optional) Number of iterations to perform maximally.
quiet - Do not show fit processing. selected - Apply fit to selected data points only. nodata - Take also models into account which are in groups containing no data. May be usefull when building complex models refering one to other. ftol - Tolerance when to stop minimization. Default: 1E-4 iterstop - Stop when key 'q' pressed. Default true.
All inputs/options may be set with the "set" command. The command prefix is "minimize".
This command is intended as a meta-fit utility which allows to minimize the data/model relation using different metrics, e.g. the chi2-metric represents quadratic distance measurements.
Changes parameter values in environment according minimisation result.
> model, "sin+lin", 2 > minimize,chi2 -> fit result > plot,data+model,res
$Id: cafe_minimize.pro,v 1.5 2005/02/16 13:37:18 goehler Exp $
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