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Topic: Optimization
Replies: 6   Last Post: Feb 27, 2013 10:42 AM

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 Carlos Alejandro Perez Lasso Posts: 3 Registered: 11/21/12
Re: Optimization
Posted: Feb 27, 2013 10:24 AM
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Alan_Weiss <aweiss@mathworks.com> wrote in message <k909dk\$77l\$1@newscl01ah.mathworks.com>...
> On 11/22/2012 2:16 PM, Matt J wrote:
> > "Carlos Alejandro Perez Lasso" <carlosalejandro85@gmail.com> wrote in
> > message <k8lisn\$aqf\$1@newscl01ah.mathworks.com>...

> >>
> >> I will try lsqcurvefit and see what happens. Regarding the objective
> >> function, it doesn't have quantizing operations like the once you
> >> described above. It does contain operations that write python scripts
> >> to produce input files for running Abaqus simulation and retrieve
> >> information once the simulation is done.

> > =================
> >
> > It seems like it would be hard to know in advance whether such a
> > function was even differentiable. As for local flatness, an easy test
> > you can do is
> >
> > small=1e-6;
> >
> > for i=1:N
> > f(x)-f(x+small*rand(size(x))) end
> >
> > If this returns N zeros, it's a strong sign know your objective
> > function f() is locally flat.

>
> You might want to consult the documentation on optimizing simulations
> for suggestions:
> http://www.mathworks.com/help/optim/ug/optimizing-a-simulation-or-ordinary-differential-equation.html
>
> Alan Weiss
> MATLAB mathematical toolbox documentation

Hi Alan and Matt,

I'm nearly done with my master thesis and I wanted to thank you both because the information you provided was really helpful. I found the answer in the section 'Set Larger Finite Differences'.

Thanks a lot.

Carlos Alejandro Perez

Date Subject Author
11/21/12 Carlos Alejandro Perez Lasso
11/21/12 Matt J
11/22/12 Carlos Alejandro Perez Lasso
11/22/12 Matt J
11/26/12 Alan Weiss
2/27/13 Carlos Alejandro Perez Lasso
2/27/13 Alan Weiss

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