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

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 Alan Weiss Posts: 1,430 Registered: 11/27/08
Re: Optimization
Posted: Feb 27, 2013 10:42 AM

On 2/27/2013 10:24 AM, Carlos Alejandro Perez Lasso wrote:
> 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

Thanks for letting us know. I'm always happy when my documentation helps
someone.

Alan Weiss
MATLAB mathematical toolbox documentation

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