Re: [eigen] Parameters in Levenberg Marquard algorithm of wrong type?

["Claas H. Köhler" <claas.koehler@xxxxxx>]

Hi Thomas!

Thanks for the support. If you are busy, I can also suggest a patch and 
send it to you for review, since I had to make some changes already to 
make my interface compile.

While looking at the code, some quesions arose:

- Is there a reason why all local temporary variables (e.g temp, temp1, 
pnorm...) are defined as class members, instead of defining locally 
where needed?

- There are some expressions like e.g. pnorm / Scalar(0.1), probably 
because the original code defined 0.1 as static constant. Would it not 
improve readability to replace this by Scalar(10.) * pnorm?

Regards
Claas


On 16/03/12 20:16, orzel@xxxxxxxxxxxxxxx wrote:
> Mmh, indeed, i've never considered complex with those. You probably
> right, I'll check about patching this
>
> Thomas
>
> On 15/03/2012 18:34, "Claas H. Köhler" wrote:
> > Hi!
> >
> > Has anybody ever tried to use the LevenbergMarquardt class of the
> > unsupported NonLinearOptimization module with complex values? I am
> > asking, because all parameters specified in the Parameters struct are
> > of type Scalar, which would result in std::complex<double>  values.
> > However, if I am not mistaken, these values should be real quantities,
> > even if the underlying problem is complex.
> >
> > Furthermore comparisons of the form
> > if (parameters.ftol<  0.) {...}
> > are used, while operator<  should not be defined for complex values at
> > all.
> >
> > Would it not be preferable to use NumTraits<Scalar>::Real instead for
> > the parameters?
> >
> >
> > Regards
> > Claas

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