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Optimization module
Posted 1 sept. 2009, 11:48 UTC−4 2 Replies
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Hi,
Does anyone know where can I obtain information and user manuals for the optimization module in Comsol 3.5a? I have a design problem which is similar to a topology optimization problem. I saw there is an optimization mode in Comsol but I have no idea how to make use of it or don't even know it is useful at all.
Thanks for the information.
John
Does anyone know where can I obtain information and user manuals for the optimization module in Comsol 3.5a? I have a design problem which is similar to a topology optimization problem. I saw there is an optimization mode in Comsol but I have no idea how to make use of it or don't even know it is useful at all.
Thanks for the information.
John
2 Replies Last Post 2 sept. 2009, 02:13 UTC−4
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Posted:
2 decades ago
A user's guide for the SNOPT 7 optimizer can be found at:
www.cam.ucsd.edu/~peg/papers/sndoc7.pdf
From the abstract, "SNOPT finds solutions that are locally optimal," it uses a gradient approach.
In our experience the COMSOL optimizer code is good if you are optimizing (perhaps) a few parameters. However if you have a dozen parameters then it will probably require a Matlab script and the Matlab 'Optimization Toolbox' (e.g. use a GA).
Regards,
smoss
www.cam.ucsd.edu/~peg/papers/sndoc7.pdf
From the abstract, "SNOPT finds solutions that are locally optimal," it uses a gradient approach.
In our experience the COMSOL optimizer code is good if you are optimizing (perhaps) a few parameters. However if you have a dozen parameters then it will probably require a Matlab script and the Matlab 'Optimization Toolbox' (e.g. use a GA).
Regards,
smoss
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Posted:
2 decades ago
Hi
I use it regularly, for the doc it should be in the .../doc folder, if you have the option. I agree with Moss that if you have up to a dozen variables its quickly set up, allthough the "variable"GUI window in 3.5a has some limitations, such as no "MOVE UP/DOWN" and when yuo enter many variables you always have to "apply" each two, as the list is too short, and is only updated after an apply.
But its true that for many variables (I use up to about 40 for my Zernike) a script i easier.
In anycase you can always do otimising without the toolbox, at least for 1-2 variables (otherwise you will find yourself rewriting the module), you can find some examples in an otherwise highly recommendable book to understand COMSOL internals such as:
www.comsol.com/academic/books/mmwfem/
good luck
Ivar
I use it regularly, for the doc it should be in the .../doc folder, if you have the option. I agree with Moss that if you have up to a dozen variables its quickly set up, allthough the "variable"GUI window in 3.5a has some limitations, such as no "MOVE UP/DOWN" and when yuo enter many variables you always have to "apply" each two, as the list is too short, and is only updated after an apply.
But its true that for many variables (I use up to about 40 for my Zernike) a script i easier.
In anycase you can always do otimising without the toolbox, at least for 1-2 variables (otherwise you will find yourself rewriting the module), you can find some examples in an otherwise highly recommendable book to understand COMSOL internals such as:
www.comsol.com/academic/books/mmwfem/
good luck
Ivar