I did this a while back, see here https://bitbucket.org/cpraveen/deal_ii/src/865f1c963f1089a870054bebf7180c9712e93da8/step-15-sacado/?at=master
Best praveen On Thu, Aug 24, 2017 at 8:26 PM, Wolfgang Bangerth <[email protected]> wrote: > > I would like to get a feeling in working with Sacado, and would like to >> try it on example 15. According to my understanding I now have to treat the >> boundary conditions on my own, and not by using the ConstraintMatrix. Is >> that still true, or was there an update since 2008? >> > > I suspect that you are referencing a particular comment in step-33, but > it's been so long that I can't recall what that program does. Can you point > out what you have in mind? > > In general, as long as you have Dirichlet boundary conditions, they can be > handled by ConstraintMatrix at the time when the local matrix is > distributed into the global matrix, and that happens after all of the > Sacado magic happens -- you get the local matrix out of Sacado and then > copy it into the global matrix. > > > Furthermore, now the function F() is depending on the gradient of u, and >> not as in example 33 depending on u, else it should look like exactly in >> example 33 (in both examples we have \nabla F(u)). Is that correct? >> Nevertheless I assume that I need the numerical flux function due to having >> to check the dangling nodes. >> > > You can also handle hanging nodes as is always done, via ConstraintMatrix. > step-33 does it differently not because that is necessary but because the > author decided that he could. > > I think that using Sacado (or in general, automatic differentiation) > should be relatively straightforward in step-15, in particular because the > residual is already computed there. I'd just give it a try and see what is > necessary. You may want to use the current developer version of deal.II -- > there have been numerous changes in recent weeks to make AD easier to use > in the FEValues class, in particular through functions such as > FEValues::get_function_{values,gradients}. > > Using AD in step-15 is an interesting project. If you make it work, would > you mind sending the assembly function to the mailing list? I think it > would make for a great section in the "Possibilities for extensions" > section of step-15! > > Best > W. > > -- > ------------------------------------------------------------------------ > Wolfgang Bangerth email: [email protected] > www: http://www.math.colostate.edu/~bangerth/ > > -- > The deal.II project is located at http://www.dealii.org/ > For mailing list/forum options, see https://groups.google.com/d/fo > rum/dealii?hl=en > --- You received this message because you are subscribed to the Google > Groups "deal.II User Group" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
