help-gsl
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Help-gsl] non-linear least squares fitting


From: Joakim Hove
Subject: Re: [Help-gsl] non-linear least squares fitting
Date: Fri, 08 Apr 2005 12:44:51 +0200
User-agent: Gnus/5.1006 (Gnus v5.10.6) Emacs/21.2 (gnu/linux)

<Disclaimer>
These ideas are all untested
</Disclaimer>

I would recomend creating struct containing the relevant flags and
default values, and then pass a pointer to such an instance as the
void parameter in the fitting routines - that way you avoid the global
variables.

To ensure[1] that the parameters are not changed I would set the 
jacobian for those parameters which should be fixed forcibly to zero.


[1]: I don't know the details of the algorithm, this might not be
     sufficient; and it is probably *not* optimal.



> PS. The manual text on the non-linear least squares fitting follows from the
> section on multidimensional minimization.  But in this case, I find the
> notion of parameters and x values to be backwards. Most would expect "x" to
> be the name of the data point, and not the parameter to be minimized.  

I fully agree :-)

HTH - Joakim


-- 
Joakim Hove
hove AT ift uib no                 /    
Tlf: +47 (55 5)8 27 90            /     Stabburveien 18          
Fax: +47 (55 5)8 94 40           /      N-5231 Paradis           
http://www.ift.uib.no/~hove/    /       55 91 28 18 / 92 68 57 04





reply via email to

[Prev in Thread] Current Thread [Next in Thread]