Is there then a way to use LinearOperator as Input for a preconditioner? Else I still have to form the full system matrix (which I would like to avoid).
Am Mittwoch, 24. Juli 2019 13:43:09 UTC+2 schrieb Daniel Arndt: > > On the other hand, would it be sufficient to unroll the >>>> residual-calculation, i.e. if the residual is F(u) = nabla^2 u + f, to >>>> write (in the cell-loop): (nabla^2(u + eps*src) + f - nabla^2u - >>>> f)/epsilon? Or would that lead to wrong results? >>>> >>> >>> It is sufficient to only change compute_diagonal() to use the MatrixFree >>> framework. Passing multiple vectors at once might be a little bit more >>> difficult to implement. >>> >> Could you elaborate on that further (changing the diagonal value)? >> > > Oh, that was a typo. I meant that you only have to implement > calculate_residual and can leave the rest of you LinearOperator as is. > > Best, > Daniel > -- 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]. To view this discussion on the web visit https://groups.google.com/d/msgid/dealii/faa5a96a-683c-4c90-a3a9-3f1d0bd38be1%40googlegroups.com.
