Hello Naren! you can use the `FEFieldFunction` <https://www.dealii.org/current/doxygen/deal.II/classFunctions_1_1FEFieldFunction.html> class for this purpose. It will interpret your finite element solution as a continuous function via interpolation. You can use it as a representation of your fine solution.
This class needs a `DoFHandler` object, your finite element solution, and the mapping collection. If you want to store your reference solution on your file system, you would need to make use of the serialization capabilities of the `Triangulation` <https://www.dealii.org/current/doxygen/deal.II/classTriangulation.html#a2f0c10f7a8cd32d961e9367173685047> and `Vector` <https://www.dealii.org/current/doxygen/deal.II/classVector.html#a9c9b9333d11630bf0fc82a7957e0d1c1> classes, and then reconstruct the dependencies for the `FEFieldFunction` representation. For parallel distributed application, you would need to make use of a `SolutionTransfer` <https://www.dealii.org/current/doxygen/deal.II/classparallel_1_1distributed_1_1SolutionTransfer.html#ad36ed9c068828e1beb0d1a87d7c76ecd> object. I hope this helps! Marc On Friday, June 4, 2021 at 10:51:49 AM UTC-6 [email protected] wrote: > Hello, > > How do I compute the L2 (in space and time) convergence rates when the > exact solution is unknown? I plan on computing a solution using a fine grid > and time step and then using that as my exact solution. How could I "save" > this solution to use it when computing the L2 error in space and time? If > it were only space, then I understand that I could use solution transfer, > but I'm unsure how to deal with the temporal variable. > > Thank you! > > Naren Vohra > -- 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/d4d8f9df-d89f-4908-ae7b-fd1f04096805n%40googlegroups.com.
