Dear Luca, Markus and Michael, Thank you for the suggestions! I'll follow Luca's idea - it sounds to be the most general. Computing the derivatives analytically with any of the symbolic calculus packages in my particular case is not reasonable, but still I want to have the derivative to be exact, and not approximated via the finite differences. In any case, thanks you all guys!
Regards, Slawa Thursday, September 2, 2010, 17:36, you wrote: MR> Hi there, MR> Another possibility which might work for you would be to calculate the MR> derivative explicitly (possibly using a symbolic math package if the MR> function is involved) and create a Function<dim> which is the MR> derivative. Since Function<dim> is user defined it seems like in many MR> cases the user could do this, however it might not be suitable for MR> your application. MR> Cheers, MR> Michael MR> On Thu, Sep 2, 2010 at 5:22 PM, Markus Bürg <[email protected]> wrote: >> Hello Slawa, >> >> as far as I know there is no easy way of getting the derivative of a >> Function<dim> object with Sacado, since (of course) Trilinos does not know >> the deal.II Function<dim> object. I think the easiest way for you would be >> to use the AutoDerivativeFunction class from deal.II. If you do not want to >> do this, please have a look in tutorial step-33 to see how to use Sacado. >> >> Best Regards, >> Markus >> >> >> >> Am 02.09.10 12:41, schrieb Svyatoslav Gladkov: >>> >>> Greetings! >>> >>> I have rather naive question about automatic differentiation in >>> deal.II: >>> Suppose I have a scalar function derived from Function<dim>. How can I >>> compute derivative (gradient) of this function in all quadrature >>> points with Sacado? >>> >>> Regards, >>> Slawa >>> >>> _______________________________________________ >>> dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii >>> >>> >> >> _______________________________________________ >> dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii >> MR> _______________________________________________ MR> dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii -- Best regards, 02.09.2010 Svyatoslav Gladkov, Kharkov, UKRAINE 18:19 _______________________________________________ dealii mailing list http://poisson.dealii.org/mailman/listinfo/dealii
