Cheater, see the discussion here
http://meta.tex.stackexchange.com/questions/228/ive-just-been-told-i-have-to-write-a-minimal-example-what-is-that
on 'minimal working example'. In debugging code, you need to sort the
wheat from the chaff (rather like Newton-Raphson does), cut out the
extraneous bits until you have a small bit of code that reproduces the
error/problem you are seeing. At that point, if you are still at nines,
please post a question with the code. Most times you won't need to,
because you will have found and fixed the problem.
cheater cheater <cheater00 at gmail.com> writes:
> Indeed, I do have this overflow there. Interesting. Maybe I should try
> substituting all arbitrary values for some sort of smallest-possible
> floating point value? But then I could get an underflow, right? All of
> the parameters I use are of positive exponents, so I shouldn't get
> overflows this way... let me think about it for a second.
>
> But really, the problem is that lsquares is marking those values as
> arbitrary. It's using newton-raphson after all - it should have some
> internal state where those "arbitrary" values do compute to something.
No, if you recall, Newton-Raphson inverts the Jacobian/solves a system
of linear equations at each iteration. This is likely where the arbitary
constants are appearing. This means your starting points, model or both
are likely poorly specified.
--
Leo Butler <l_butler at users.sourceforge.net>
SDF Public Access UNIX System - http://sdf.lonestar.org