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fitter - Constructor



Package utility
Module fitting
Tool fitter


Construct fitting tool


Synopsis
fitter(n, type, colfac, lmfac, host, forcenewserver)


Arguments

n in number of unknowns
    Allowed: integer
    Default: 0
type in type of solution
    Allowed: coded value as string. Allowed: real, complex, separable, asreal, conjugate
    Default: 'real'
colfac in collinearity factor
    Allowed: positive float
    Default: 1e-8
lmfac in Levenberg-Marquardt factor
    Allowed: positive float
    Default: 1e-3
host in name of host to run on
    Allowed: string
    Default: ''
forcenewserver in is a new process needed
    Allowed: bool
    Default: F


Returns
fitting tool or fail


Description
Create a fitting tool. The tool can be created without arguments (in which case it is assumed to be a real fitter), or with the arguments specifying the number of unknowns to be solved for (a number not relevant in practice); and the type of solution: real, complex, conjugate (complex with both the unknown and its conjugate in the condition equations), separable complex, asreal complex with the real and imaginary part seen as independent unknowns. All solutions need a model (specified as a functional. All solutions are done using an SVD type method. A collinearity factor can be specified, which is in essence the sine squared of the minimum angle between two normal equation columns that are still to be considered independent. For automatic non-linear solutions, a Levenberg-Marquardt factor (see Note 224) is used, which can be specified as well.

In the case of non-linear solutions that have to be handled by the system, an initial estimate for the model parameters is necessary.

A default fitter is always created, with an id that does not have to be specified. (see fitter method for sub constructors).





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2006-10-15