Re: Constrained Fitting

[davidf(at)dfanning.com (David Fanning)]

Lanette Friesen (lfriesen@irus.rri.on.ca) writes:

> I've been testing  a number of the curve fitting routines in IDL with my
> data.  I've been using mainly CURVEFIT and LMFIT.  I have three
> parameters in a bi-exponential fit and I need to put constraints on
> these parameters.  As far as I can tell, putting constraints on the
> parameters is not possible with the current fitting routines.  Am I
> missing something?  Is there a different fitting routine that I haven't
> found that allows either non-linear least squares fitting or something
> like it with constrained fitting parameters?

Anyone who is even *thinking* about curve fitting better
get themselves over to Craig Markwardt's page and check
out what he is making available:

   http://cow.physics.wisc.edu/~craigm/idl/fitting.html

I don't know how IDL gets away without including his
stuff in the basic product. :-)

Cheers,

David

-- 
David Fanning, Ph.D.
Fanning Software Consulting
Phone: 970-221-0438 E-Mail: davidf@dfanning.com
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