discretefunction.hh

#ifndef DUNE_FEM_FUNCTION_TUPLEDISCRETEFUNCTION_DISCRETEFUNCTION_HH
#define DUNE_FEM_FUNCTION_TUPLEDISCRETEFUNCTION_DISCRETEFUNCTION_HH
 
#include <string>
#include <tuple>
#include <utility>
 
#include <dune/common/hybridutilities.hh>
 
#include <dune/fem/common/stackallocator.hh>
#include <dune/fem/function/common/discretefunction.hh>
#include <dune/fem/function/common/scalarproducts.hh>
#include <dune/fem/function/localfunction/mutable.hh>
#include <dune/fem/function/tuplediscretefunction/functor.hh>
 
#include <dune/fem/function/tuplediscretefunction/dofvector.hh>
#include <dune/fem/space/combinedspace.hh>
 
namespace Dune
{
 
  namespace Fem
  {
 
    template< class ... DiscreteFunctions >
    class TupleDiscreteFunction;
 
    // DiscreteFunctionTraits
    // ----------------------
 
    template< class ... DiscreteFunctions >
    struct DiscreteFunctionTraits< TupleDiscreteFunction< DiscreteFunctions ... > >
      : public DefaultDiscreteFunctionTraits<
          TupleDiscreteFunctionSpace< typename DiscreteFunctions::DiscreteFunctionSpaceType ... >,
          TupleDofVector< typename DiscreteFunctions::DofVectorType ... >
          >
    {
      typedef TupleDiscreteFunction< DiscreteFunctions ... > DiscreteFunctionType;
      typedef MutableLocalFunction< DiscreteFunctionType > LocalFunctionType;
    };
 
 
    // TupleDiscreteFunction
    // ---------------------
 
    template< class ... DiscreteFunctions >
    class TupleDiscreteFunction
      : public DiscreteFunctionDefault< TupleDiscreteFunction< DiscreteFunctions ... > >,
        public std::tuple< DiscreteFunctions ... >
    {
      typedef TupleDiscreteFunction< DiscreteFunctions ... > ThisType;
      typedef DiscreteFunctionDefault< ThisType > BaseType;
 
      typedef ParallelScalarProduct< ThisType > ScalarProductType;
 
      typedef std::tuple< DiscreteFunctions ... > DiscreteFunctionTuple;
 
      static_assert( sizeof ... ( DiscreteFunctions ) > 0, "TupleDiscreteFunction needs at least one DiscreteFunction." );
 
    public:
      typedef decltype ( std::index_sequence_for< DiscreteFunctions ... >() ) Sequence;
 
      typedef TupleDofVector< typename DiscreteFunctions::DofVectorType ... > DofVectorType;
 
      using BaseType::space;
 
      typedef TupleDiscreteFunctionSpace< typename DiscreteFunctions::DiscreteFunctionSpaceType ... > DiscreteFunctionSpaceType;
 
      template< int i >
      struct SubDiscreteFunction
      {
        typedef typename std::tuple_element< i, DiscreteFunctionTuple >::type Type;
      };
 
      TupleDiscreteFunction ( const std::string &name,
                              const DiscreteFunctionSpaceType &dfSpace,
                              DofVectorType &dofVector )
        : TupleDiscreteFunction ( name, dfSpace, dofVector, Sequence() ) {}
 
      TupleDiscreteFunction ( const std::string &name,
                              const DiscreteFunctionSpaceType &dfSpace )
        : TupleDiscreteFunction ( name, dfSpace, Sequence() ) {}
 
      // copy constructor
      TupleDiscreteFunction ( const ThisType &other )
        : TupleDiscreteFunction ( "copy of "+other.name(), other.space(), Sequence() )
      {
        dofVector_ = other.dofVector();
      }
 
      // move constructor
      TupleDiscreteFunction ( ThisType&& other )
        : BaseType ( static_cast< BaseType && >( other ) ),
          DiscreteFunctionTuple( std::move( other ) ),
          dofVector_( std::move( other.dofVector_ ) )
      {}
 
      TupleDiscreteFunction () = delete;
      ThisType &operator= ( const ThisType & ) = delete;
 
      DofVectorType &dofVector () { return dofVector_; }
      const DofVectorType &dofVector () const { return dofVector_; }
 
      template< int i >
      typename SubDiscreteFunction< i >::Type& subDiscreteFunction()
      {
        return std::get< i >( *this );
      }
 
      template< int i >
      const typename SubDiscreteFunction< i >::Type& subDiscreteFunction() const
      {
        return std::get< i >( *this );
      }
 
      void enableDofCompression ()
      {
        Hybrid::forEach( Sequence{}, [ & ]( auto i ){  std::get< i >( *this ).enableDofCompression(); } );
      }
 
    protected:
 
      template< std::size_t ... I >
      TupleDiscreteFunction ( const std::string &name, const DiscreteFunctionSpaceType &space, std::index_sequence< I ... > )
        : BaseType( name, space ),
          DiscreteFunctionTuple(
            typename SubDiscreteFunction< I >::Type(
              name + "_comp_" + std::to_string( I ), space.template subDiscreteFunctionSpace< I >()
              ) ... ),
          dofVector_( std::get< I >( *this ).dofVector() ... )
      {}
 
      template< std::size_t ... I >
      TupleDiscreteFunction ( const std::string &name, const DiscreteFunctionSpaceType &space,
                              DofVectorType &dofVector, std::index_sequence< I ... > )
        : BaseType( name, space ),
          DiscreteFunctionTuple(
            typename SubDiscreteFunction< I >::Type(
              name + "_comp_" + std::to_string( I ), space.template subDiscreteFunctionSpace< I >(),
              std::get< I >( dofVector ) ) ... ),
          dofVector_( dofVector )
      {}
 
      DofVectorType dofVector_;
    };
 
  } // namespace Fem
 
} // namespace Dune
 
#endif // #ifndef DUNE_FEM_FUNCTION_TUPLEDISCRETEFUNCTION_DISCRETEFUNCTION_HH