[Dune] Re: Anfrage 2d integration in 3d grids.

[Robert Kloefkorn]

Leidenberger Patrick wrote:
> Hi Robert, hi Christian,
> 
> Thanks a lot!!!! For the help a the tips for my code.
> 
> Please allow me two more questions:
> What have to be changed in the integration if I want to use the intersection iterator 

The code look something like this (just a sample):

Lets say you selected the LeafGridPart, which indirectly selects the
leaf index set and appropriate interators (i.e. LeafIterator,
LeafIntersectionIterator, have a look dune-grid/grid/common/gridpart.hh ) :


GridType grid(...);

typedef LeafGridPart<GridType> GridPartType;
GridPartType gridPart(grid);

// get type of corresponding iterator
typedef typename GridPartType :: template Codim<0> :: IteratorType
IteratorType;

// loop over all entities belonging to choosen sub set of grid
IteratorType endit = gridPart.template end<0> ();
for(IteratorType it = gridPart.template begin<0> ();
    it != endit; ++it)
{
  // select corresponding intersection iterator
  typedef typename GridPartType :: IntersectionIteratorType
    IntersectionIteratorType ;

  IntersectionIteratorType endnit = gridPart.iend(*it);
  for (IntersectionIteratorType nit = gridPart.ibegin(*it);
       nit != endnit; ++nit)
  {
    // get geometry of intersection
    const Geometry & faceGeo = nit.intersectionGlobal();

    // from here it's the same as in the other example before
  }
}

Note: I just typed this piece of code so it might not work at once when
copied to source file.

Regards

R

-- 

  Robert Klöfkorn           <robertk at mathematik.uni-freiburg.de>

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