transformedfiniteelementmixin.hh

// -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
// vi: set et ts=4 sw=2 sts=2:
 
// SPDX-FileCopyrightText: Copyright © DUNE Project contributors, see file AUTHORS.md
// SPDX-License-Identifier: LicenseRef-GPL-2.0-only-with-DUNE-exception OR LGPL-3.0-or-later
 
#ifndef DUNE_FUNCTIONS_FUNCTIONSPACEBASES_TRANSFORMEDFINITEELEMENTMIXIN_HH
#define DUNE_FUNCTIONS_FUNCTIONSPACEBASES_TRANSFORMEDFINITEELEMENTMIXIN_HH
 
namespace Dune::Functions::Impl {
 
template<class FEImplementation, class ReferenceLocalBasisTraits>
class TransformedLocalBasis
{
  public:
    using Traits = ReferenceLocalBasisTraits;
 
    TransformedLocalBasis(FEImplementation const& feImpl)
      : feImpl_(&feImpl)
    {}
 
  public:
    auto size() const
    {
      return feImpl_->size();
    }
 
    void evaluateFunction(const typename Traits::DomainType &x,
                          std::vector<typename Traits::RangeType> &out) const
    {
      feImpl_->referenceLocalBasis().evaluateFunction(x, rangeBuffer_);
      out.resize(size());
      feImpl_->transform(rangeBuffer_, out);
    }
 
    void evaluateJacobian(const typename Traits::DomainType &x,
                          std::vector<typename Traits::JacobianType> &out) const
    {
      feImpl_->referenceLocalBasis().evaluateJacobian(x, jacobianBuffer_);
      out.resize(size());
      feImpl_->transform(jacobianBuffer_, out);
    }
 
    template<class TT,
             std::enable_if_t<std::is_same_v<TT, typename Traits::HessianType>, int> = 0>
    void evaluateHessian(const typename Traits::DomainType &x,
                         std::vector<TT> &out) const
    {
      feImpl_->referenceLocalBasis().evaluateHessian(x, hessianBuffer_);
      out.resize(size());
      feImpl_->transform(hessianBuffer_, out);
    }
 
    void partial(std::array<unsigned int, Traits::dimDomain> const &order,
                 const typename Traits::DomainType &x,
                 std::vector<typename Traits::RangeType> &out) const
    {
      feImpl_->referenceLocalBasis().partial(order, x, rangeBuffer_);
      out.resize(size());
      feImpl_->transform(rangeBuffer_, out);
    }
 
    auto order() const { return feImpl_->referenceLocalBasis().order(); }
 
  private:
    FEImplementation const* feImpl_;
    mutable std::vector<typename Traits::RangeType> rangeBuffer_;
    mutable std::vector<typename Traits::JacobianType> jacobianBuffer_;
    mutable std::vector<typename Traits::HessianType> hessianBuffer_;
};
 
 
 
template<class FEImplementation, class ReferenceLocalBasisTraits>
class TransformedFiniteElementMixin
{
  public:
    TransformedFiniteElementMixin()
      : tlb_(this->asImpl())
    {}
 
    TransformedFiniteElementMixin(TransformedFiniteElementMixin const& other)
    : TransformedFiniteElementMixin()
    {}
 
    const FEImplementation& asImpl() const
    {
      return *(static_cast<FEImplementation const*>(this));
    }
 
    auto const& localBasis() const
    {
      return tlb_;
    }
 
  protected:
    TransformedLocalBasis<FEImplementation, ReferenceLocalBasisTraits> tlb_;
};
 
} // end namespace Dune::Functions::Impl
 
#endif