.. _program_listing_file_src_pcms_coupler_field_serializer.h:

Program Listing for File field_serializer.h
===========================================

|exhale_lsh| :ref:`Return to documentation for file <file_src_pcms_coupler_field_serializer.h>` (``src/pcms/coupler/field_serializer.h``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   #ifndef PCMS_FIELD_SERIALIZER_H
   #define PCMS_FIELD_SERIALIZER_H
   
   #include "pcms/field/field.h"
   #include "pcms/utility/arrays.h"
   #include "pcms/utility/memory_spaces.h"
   #include "pcms/utility/types.h"
   #include <Kokkos_Core.hpp>
   
   namespace pcms
   {
   
   // Packs a field's owned values into, and unpacks them from, an exchange
   // buffer, through the field's DOFAccess. Any field with DOFAccess is
   // exchanged this way. Backends that need extra work on receive (e.g.,
   // synchronizing replicas) do it in DOFAccess::SetOwnedValues.
   template <typename T>
   class FieldSerializer
   {
   public:
     int Serialize(const Field<T>& field, Rank1View<T, HostMemorySpace> buffer,
                   Rank1View<const LO, HostMemorySpace> permutation) const
     {
       const auto data = field.GetDOFHolderDataHost().GetValues();
       if (buffer.size() > 0) {
         const LO num_dof = static_cast<LO>(data.extent(0));
         const LO num_comp = static_cast<LO>(data.extent(1));
         for (LO i = 0; i < num_dof; ++i) {
           if (permutation[i] >= 0) {
             for (LO c = 0; c < num_comp; ++c) {
               buffer[permutation[i] * num_comp + c] = data(i, c);
             }
           }
         }
       }
       return static_cast<int>(buffer.size());
     }
   
     void Deserialize(Field<T>& field, Rank1View<const T, HostMemorySpace> buffer,
                      Rank1View<const LO, HostMemorySpace> permutation) const
     {
       const auto& layout = field.GetLayout();
       const LO num_dof = layout.GetNumOwnedDofHolder();
       const LO num_comp = layout.GetNumComponents();
       // We initialize with local data so that
       // data that doesn't get received from deserialized
       // doesn't get zeroed out. Long term FIXME
       // is to make Get/SetData operate over only part of the
       // arrays
       const auto current = field.GetDOFHolderDataHost().GetValues();
       Kokkos::View<T*, HostMemorySpace> sorted("sorted", layout.OwnedSize());
       for (LO i = 0; i < num_dof; ++i) {
         for (LO c = 0; c < num_comp; ++c) {
           sorted[i * num_comp + c] = current(i, c);
         }
       }
       for (LO i = 0; i < num_dof; ++i) {
         if (permutation[i] >= 0) {
           for (LO c = 0; c < num_comp; ++c) {
             sorted[i * num_comp + c] = buffer[permutation[i] * num_comp + c];
           }
         }
       }
       field.SetDOFHolderDataUncheckedHost(
         Rank2View<const T, HostMemorySpace>(sorted.data(), num_dof, num_comp));
     }
   };
   
   } // namespace pcms
   
   #endif // PCMS_FIELD_SERIALIZER_H