VectorBackend.hpp

#pragma once
 
#include <dune/istl/bvector.hh>
#include <dune/functions/backends/istlvectorbackend.hh>
 
#include <amdis/Output.hpp>
#include <amdis/common/FakeContainer.hpp>
#include <amdis/linearalgebra/VectorBase.hpp>
#include <amdis/typetree/MultiIndex.hpp>
 
namespace AMDiS
{
  template <class T, class = void>
  struct BlockVectorType
  {
    using type = Dune::FieldVector<T,1>;
  };
 
  template <class T>
  struct BlockVectorType<T, typename T::field_type>
  {
    using type = T;
  };
 
  template <class T>
  class ISTLBlockVector
      : public VectorBase<ISTLBlockVector<T>>
  {
    using Self = ISTLBlockVector;
 
  public:
    using BaseVector = Dune::BlockVector<typename BlockVectorType<T>::type>;
 
    using block_type = typename BaseVector::block_type;
 
    using value_type = T;
 
    using field_type = typename block_type::field_type;
 
    using size_type  = typename BaseVector::size_type;
 
  public:
    template <class Comm,
      Dune::disableCopyMove<ISTLBlockVector,Comm> = 0>
    explicit ISTLBlockVector(Comm const&) {}
 
    ISTLBlockVector() = default;
 
    BaseVector const& vector() const
    {
      return vector_;
    }
 
    BaseVector& vector()
    {
      return vector_;
    }
 
    std::size_t size() const
    {
      return vector_.size();
    }
 
    // NOTE: this resize works recursively on the hierarchy of the vector
    template <class Basis>
    void init(Basis const& basis, bool clear)
    {
      Dune::Functions::istlVectorBackend(vector_).resize(basis);
      if (clear)
        vector_ = 0;
    }
 
    template <class MultiIndex>
    value_type& at(MultiIndex const& idx)
    {
      return Dune::Functions::istlVectorBackend(vector_)[idx];
    }
 
    template <class MultiIndex>
    value_type const& at(MultiIndex const& idx) const
    {
      return Dune::Functions::istlVectorBackend(vector_)[idx];
    }
 
 
    Self& axpy (const value_type& alpha, const Self& x)
    {
      vector_.axpy(alpha, x.vector_);
      return *this;
    }
 
    Self& aypx (const value_type& alpha, const Self& x)
    {
      vector_ *= alpha;
      vector_ += x.vector_;
      return *this;
    }
 
    void set (const value_type& alpha)
    {
      vector_ = alpha;
    }
 
    void scale (const value_type& alpha)
    {
      vector_ *= alpha;
    }
 
 
  private:
    BaseVector vector_;
  };
 
 
  namespace Recursive
  {
    template <class T>
    struct ForEach<ISTLBlockVector<T>> : ForEach<VectorBase<ISTLBlockVector<T>>> {};
 
    template <class T>
    struct Transform<ISTLBlockVector<T>> : Transform<VectorBase<ISTLBlockVector<T>>> {};
 
    template <class T>
    struct InnerProduct<ISTLBlockVector<T>> : InnerProduct<VectorBase<ISTLBlockVector<T>>> {};
 
  } // end namespace Recursive
} // end namespace AMDiS