coordinatefunctions.hh

#ifndef DUNE_ACFEM_COORDINATEGRIDFUNCTIONS_HH
#define DUNE_ACFEM_COORDINATEGRIDFUNCTIONS_HH
 
#include "../functions/gridfunctionwrapper.hh"
 
namespace Dune {
 
  namespace ACFem {
 
    template<class Field, unsigned dim>
    class IdentityFunction
      : public Fem::Function<Fem::FunctionSpace<Field, Field, dim, dim>, IdentityFunction<Field, dim> >
    {
      typedef IdentityFunction ThisType;
      typedef Fem::Function<Fem::FunctionSpace<Field, Field, dim, dim>, ThisType> BaseType;
     public:
      typedef typename BaseType::FunctionSpaceType FunctionSpaceType;
 
      enum { dimRange  = FunctionSpaceType::dimRange  };
      enum { dimDomain = FunctionSpaceType::dimDomain };
 
      typedef typename FunctionSpaceType::RangeFieldType   RangeFieldType;
 
      typedef typename FunctionSpaceType::RangeType   RangeType;
      typedef typename FunctionSpaceType::DomainType  DomainType;
 
      typedef typename FunctionSpaceType::JacobianRangeType  JacobianRangeType;
      typedef typename FunctionSpaceType::HessianRangeType HessianRangeType;
 
      IdentityFunction() {} // we have no state
 
      void evaluate(const DomainType& x, RangeType& res) const
      {
        res = x;
      }
 
      void jacobian(const DomainType& x, JacobianRangeType& res) const
      {
        res = 0;
        for (int i = 0; i < dimDomain; ++i) {
          res[i][i] = 1.0;
        }
      }
 
      void hessian(const DomainType& x, HessianRangeType& res) const
      {
        res = 0;
      }
    };
 
    template<class Field, unsigned dim, unsigned N>
    class CoordinateFunction
      : public Fem::Function<Fem::FunctionSpace<Field, Field, dim, 1>, CoordinateFunction<Field, dim, N> >
    {
      typedef CoordinateFunction ThisType;
      typedef Fem::Function<Fem::FunctionSpace<Field, Field, dim, 1>, ThisType> BaseType;
     public:
      typedef typename BaseType::FunctionSpaceType FunctionSpaceType;
 
      enum { dimRange  = 1  };
      enum { dimDomain = FunctionSpaceType::dimDomain };
      enum { component = N };
 
      typedef typename FunctionSpaceType::RangeFieldType   RangeFieldType;
 
      typedef typename FunctionSpaceType::RangeType   RangeType;
      typedef typename FunctionSpaceType::DomainType  DomainType;
 
      typedef typename FunctionSpaceType::JacobianRangeType  JacobianRangeType;
      typedef typename FunctionSpaceType::HessianRangeType HessianRangeType;
 
      CoordinateFunction() {
        static_assert(component < (unsigned)dimDomain, "Index out of range");
      }
 
      void evaluate(const DomainType& x, RangeType& res) const
      {
        res = x[component];
      }
 
      void jacobian(const DomainType& x, JacobianRangeType& res) const
      {
        res = 0;
        res[0][component] = 1.0;
      }
 
      void hessian(const DomainType& x, HessianRangeType& res) const
      {
        res = 0;
      }
    };
 
 
  } // ACFem::
 
} // Dune::
 
 
#endif // DUN_ACFEM_GRIDFUNCITONWRAPPER_HH