ZeroOrderTest.hpp

#pragma once
 
#include <type_traits>
 
#include <amdis/GridFunctionOperator.hpp>
#include <amdis/common/StaticSize.hpp>
 
#include <dune/common/typetree/nodeconcepts.hh>
 
namespace AMDiS
{
  namespace tag
  {
    struct test {};
  }
 
  class ZeroOrderTest
  {
  public:
    ZeroOrderTest(tag::test) {}
 
    template <class CG, class Node, class Quad, class LocalFct, class Vec>
    void assemble(CG const& contextGeo, Node const& node, Quad const& quad,
                  LocalFct const& localFct, Vec& elementVector) const
    {
      static_assert(static_size_v<typename LocalFct::Range> == 1,
        "Expression must be of scalar type." );
      static_assert(Dune::TypeTree::Concept::LeafTreeNode<Node>,
        "Operator can be applied to Leaf-Nodes only");
 
      std::size_t size = node.size();
 
      for (auto const& qp : quad) {
        // Position of the current quadrature point in the reference element
        auto&& local = contextGeo.coordinateInElement(qp.position());
 
        // The multiplicative factor in the integral transformation formula
        auto factor = contextGeo.integrationElement(qp.position()) * qp.weight();
        factor *= localFct(local);
 
        auto const& shapeValues = node.localBasisValuesAt(local);
        for (std::size_t i = 0; i < size; ++i) {
          const auto local_i = node.localIndex(i);
          elementVector[local_i] += factor * shapeValues[i];
        }
      }
    }
  };
 
  template <class LC>
  struct GridFunctionOperatorRegistry<tag::test, LC>
  {
    static constexpr int degree = 0;
    using type = ZeroOrderTest;
  };
 
} // end namespace AMDiS