Using Dolfin Adjoint for Custom method to estimate the roots

[Ricardo D. Lahuerta]

Dear all,

My apologies for bothering you regarding Dolfin Adjoint issues.

I would like to know if you have some examples related to the "Lower-level interfaces."

I need to solve my problem implementing a particular type o full Newton method to estimate the roots of the problem and during the optimization process, the Dolfin Adjoint replaces my solving method when I call the reduced functional. How can I do a more low-level implementation that Dolfin Adjoint can keep my particular solution method?

Is there any example?

Best Regards,

[Simon Funke]

Hi Ricardo,

I think what you are asking is if you can add a custom solve into the dolfin-adjoint pipeline with your own Newton implementation? Is that correct?

Simon

[Ricardo D. Lahuerta]

Hello Simon,

I implemented a Generalized Displacement Control Method (GDCM) to solve instability structural problems inside o fenics. For that is not possible to use the Newton method.

I would like to use dolfin-adjoint to perform topology optimization, for that, I have to solver the adjoint problem manually for each GDCM step.

I would like to know some example that I can use dolfin-adjoint libraries to perform it.

Ricardo

[Ricardo D. Lahuerta]

Here the TAO example that I am performing using GDCM.

https://www.dropbox.com/s/pu5ox7fus4rbrjv/deformacao_viga2.avi?dl=0

The TAO solver is not working well in my examples, I don't know why.

Ricardo

[Simon Funke]

Hi Ricardo,

The most useful interface for you is probably to construct a dolfin_adjoint.ReducedFunctional or dolfin_adjoint.ReducedFunctionalNumpy. With that you can evaluate the functional and compute its derivatives at different points in the control space.

Check out the API documentation to see if this is what you need: http://www.dolfin-adjoint.org/en/latest/documentation/api.html#dolfin_adjoint.ReducedFunctional

[Ricardo D. Lahuerta]

Hello Simon,

I started to programming a ReducedFunctional for a GDCM, using libadjoint libraries.

I think I will need more information about the variables, but I appreciate a lot your time to have a look in my issue.

If you have more examples or information, it will be very welcome.

Regards,