Re: [Libmesh-users] augmented finite elements

[Tobias M. <tob...@un...>]

On 5/12/21 11:41 PM, John Peterson wrote:
>
>
> On Wed, May 12, 2021 at 4:25 PM Tobias Moehle 
> <tob...@un... <mailto:tob...@un...>> 
> wrote:
>
>     Dear all,
>
>     I hope that someone has experience or some good ideas to help me
>     out: I
>     am using a setup where the finite element basis is augmented by a
>     function which contains the most rapidly changing features of the
>     solution to allow for a considerably coarser grid.
>
>     However, when it comes to printing of the solution, I am stuck:
>       - In best case, I'd like to use a refined mesh for printing. To
>     represent the solution reasonably good, I have tried to copy the mesh
>     into another one which I refine. My initial idea was to use a child
>     class to MeshFunction to project the original solution with the
>     augmentation function onto the finer grid; but since the
>     "MeshFunction::operator()" is not virtual, one cannot overload it.
>
>
> It looks like those operator() functions aren't explicitly marked 
> virtual, but they definitely are! (Also, they are marked "override", 
> which is another clue that they are virtual.) So your approach of 
> subclassing MeshFunction sounds like a reasonable one to me... I will 
> push a commit adding the virtual keyword where it's missing.
>
Oh, that sounds very good! I actually had the impression that it is 
rather a case as discussed here: 
https://stackoverflow.com/questions/21075922/function-overriding-in-c-works-without-virtual/21076030#21076030 
just that the base-class will be called because here indirection is used!?

Than I will follow this route and hopefully also get the refinement-part 
going.

Many thanks for the fast answer!


> -- 
> John