orthonormal.hh

#ifndef DUNE_FEM_OPERATOR_PROJECTION_LOCAL_RIESZ_ORTHONORMAL_HH
#define DUNE_FEM_OPERATOR_PROJECTION_LOCAL_RIESZ_ORTHONORMAL_HH
 
#include <cassert>
#include <cstddef>
 
#include <utility>
 
#include <dune/geometry/referenceelements.hh>
 
#include "localrieszprojection.hh"
 
namespace Dune
{
 
  namespace Fem
  {
 
    // OrthonormalLocalRieszProjection
    // -------------------------------
 
    template< class BasisFunctionSet >
    class OrthonormalLocalRieszProjection
    : public LocalRieszProjection< BasisFunctionSet, OrthonormalLocalRieszProjection< BasisFunctionSet > >
    {
      typedef OrthonormalLocalRieszProjection< BasisFunctionSet > ThisType;
      typedef LocalRieszProjection< BasisFunctionSet, OrthonormalLocalRieszProjection< BasisFunctionSet > > BaseType;
 
    public:
      typedef typename BaseType::BasisFunctionSetType BasisFunctionSetType;
 
    private:
      typedef typename BasisFunctionSet::FunctionSpaceType::RangeFieldType RangeFieldType;
 
    public:
      explicit OrthonormalLocalRieszProjection ( const BasisFunctionSetType &basisFunctionSet )
        : basisFunctionSet_( std::forward< BasisFunctionSetType >( basisFunctionSet ) ),
          factor_( ratio( basisFunctionSet.entity().geometry() ) )
      {}
 
      explicit OrthonormalLocalRieszProjection ( BasisFunctionSetType &&basisFunctionSet )
        : basisFunctionSet_( std::forward< BasisFunctionSetType >( basisFunctionSet ) ),
          factor_( ratio( basisFunctionSet.entity().geometry() ) )
      {}
 
      OrthonormalLocalRieszProjection ( const ThisType & ) = default;
 
      OrthonormalLocalRieszProjection ( ThisType &&other )
        : basisFunctionSet_( std::move( other.basisFunctionSet_ ) ),
          factor_( other.factor_ )
      {}
 
      ThisType &operator= ( const ThisType & ) = default;
 
      ThisType &operator= ( ThisType &&other )
      {
        basisFunctionSet_ = std::move( other.basisFunctionSet_ );
        factor_( other.factor_ );
        return *this;
      }
 
      BasisFunctionSetType basisFunctionSet () const
      {
        return basisFunctionSet_;
      }
 
      template< class F, class LocalDofVector >
      void apply ( const F &f, LocalDofVector &dofs ) const
      {
        assert( f.size() == dofs.size() );
        const std::size_t size = dofs.size();
        for( std::size_t i = 0u; i < size; ++i )
          dofs[ i ] = factor_*f[ i ];
      }
 
    private:
      template< class Geometry >
      static RangeFieldType ratio ( const Geometry &geometry )
      {
        assert( geometry.affine() );
        const auto &referenceElement
          = Dune::ReferenceElements< typename Geometry::ctype, Geometry::mydimension >::general( geometry.type() );
        return referenceElement.volume()/geometry.volume();
      }
 
      BasisFunctionSetType basisFunctionSet_;
      RangeFieldType factor_;
    };
 
  } // namespace Fem
 
} // namepsace Dune
 
#endif // #ifndef DUNE_FEM_OPERATOR_PROJECTION_LOCAL_RIESZ_ORTHONORMAL_HH