Operations.h

#pragma once
 
#if (COUPLING_MD_ERROR == COUPLING_MD_YES)
#include <sstream>
#endif
 
namespace coupling {
namespace indexing {

template <unsigned int dim, IndexTrait... traits> unsigned int convertToScalar(const CellIndex<dim, traits...>& index) {
  if constexpr (std::is_same_v<unsigned int, typename CellIndex<dim, traits...>::value_T>) {
    return index.get();
  } else {
    // copied from deprecated coupling::IndexConversion::getCellIndex())
 
#if (COUPLING_MD_ERROR == COUPLING_MD_YES)
    if (!IndexingService<dim>::getInstance().isInitialized()) {
      throw std::runtime_error(std::string("coupling::indexing::convertToScalar: IndexingService not initialized! "));
    }
    for (unsigned d = 0; d < dim; d++)
      if (index.get()[d] < 0 || index.get()[d] > ((int)CellIndex<dim, traits...>::numberCellsInDomain[d]) - 1) {
        std::stringstream ss;
        ss << "ERROR: Indexing: Cannot convert this vector index to scalar." << std::endl;
        ss << "Faulty Index = " << index.get() << std::endl;
        ss << "My rank = " << IndexingService<dim>::getInstance().getRank() << std::endl;
        ss << "Index type = " << index.TNAME << std::endl;
        throw std::runtime_error(ss.str());
      }
#endif
 
    unsigned int i{static_cast<unsigned int>(index.get()[dim - 1])};
    for (int d = dim - 2; d > -1; d--) {
      i = (CellIndex<dim, traits...>::numberCellsInDomain[d]) * i + static_cast<unsigned int>(index.get()[d]);
    }
 
    return i;
  }
}

template <unsigned int dim, IndexTrait... traits> tarch::la::Vector<dim, int> convertToVector(const CellIndex<dim, traits...>& index) {
  if constexpr (std::is_same_v<tarch::la::Vector<dim, int>, typename CellIndex<dim, traits...>::value_T>) {
    // trivial case: convert vector to vector
    return index.get();
  } else {
    // copied from coupling::getVectorCellIndex()
 
#if (COUPLING_MD_ERROR == COUPLING_MD_YES)
    if (!IndexingService<dim>::getInstance().isInitialized()) {
      throw std::runtime_error(std::string("coupling::indexing::convertToVector: IndexingService not initialized! "));
    }
#endif
 
    tarch::la::Vector<dim, int> i{0};
    unsigned int i_sca{index.get()};
    for (int d = dim - 1; d > 0; d--) {
      i[d] = static_cast<int>(i_sca / CellIndex<dim, traits...>::divisionFactor[d]);
      i_sca -= static_cast<unsigned int>(i[d]) * CellIndex<dim, traits...>::divisionFactor[d];
    }
    i[0] = i_sca;
 
    return i;
  }
}
 
} // namespace indexing
} // namespace coupling