[BUG] Message Exchange

CMakeLists.txt

@@ -26,6 +26,9 @@ if(TEST_INTERPOLATION)
   add_executable(aether ${SRC_FILES} ${MSIS_FILES} ${MAIN_DIR}/main_test_interpolation.cpp)
 elseif(TEST_COORD)
   add_executable(aether ${SRC_FILES} ${MSIS_FILES} ${MAIN_DIR}/main_test_coord.cpp)
+elseif(TEST_EXCHANGE)
+  add_executable(aether ${SRC_FILES} ${MSIS_FILES} ${MAIN_DIR}/main_test_exchange.cpp)
+  set(USE_DOUBLE_PRECISION True)
 else()
   add_executable(aether ${SRC_FILES} ${MSIS_FILES} ${MAIN_DIR}/main.cpp)
 endif()

include/grid.h

@@ -4,6 +4,7 @@
 #ifndef INCLUDE_GRID_H_
 #define INCLUDE_GRID_H_
 
+#include <unordered_map>
 #include "mpi.h"
 
 // ----------------------------------------------------------------------------
@@ -167,6 +168,9 @@ class Grid {
   void report_grid_boundaries();
   void calc_cent_acc(Planets planet);
 
+  // Update ghost cells with values from other processors
+  void exchange(arma_cube &data, const bool pole_inverse);
+
   // Need to move these to private at some point:
 
   bool IsLatLonGrid;
@@ -334,6 +338,23 @@ class Grid {
 
   // Processed interpolation coefficients
   std::vector<struct interp_coef_t> interp_coefs;
+
+  // Initialize connections between processors
+  void init_connection();
+  // Used for message exchange
+  struct idx2d_t {
+    // Index of row and column
+    int64_t ilon;
+    int64_t ilat;
+    // -1 if message crosses the north/south pole, 1 otherwise
+    int inverse;
+  };
+  // Store which processor needs its value
+  std::unordered_map<int, std::vector<struct interp_coef_t>> exch_send;
+  // Store which processor it gets value from
+  std::unordered_map<int, std::vector<struct idx2d_t>> exch_recv;
+  // The communicator for set of processors whose iMembers are equal
+  MPI_Comm grid_comm;
 };
 
 #endif  // INCLUDE_GRID_H_

include/neutrals.h

@@ -420,6 +420,7 @@ class Neutrals {
      \param grid The grid to define the neutrals on
    **/
   bool exchange(Grid &grid);
+  bool exchange_old(Grid &grid);
 
   /**********************************************************************
    \brief add eddy contributions to vertical acceleration

include/tools.h

@@ -237,4 +237,10 @@ bool is_nan_inf(double value);
 
 std::vector<int> indef_vector(arma_cube cube);
 
+// --------------------------------------------------------------------------
+// Project a point described by lon and lat to a point on a surface of the 2-2-2 cube
+// --------------------------------------------------------------------------
+
+arma_vec sphere_to_cube(precision_t lon_in, precision_t lat_in);
+
 #endif  // INCLUDE_TOOLS_H_

src/exchange_messages.cpp

@@ -413,7 +413,7 @@ Grid::messages_struct Grid::make_new_interconnection(int64_t iDir,
 //   5. Unpack variables from all sides
 // -----------------------------------------------------------------------------
 
-bool Neutrals::exchange(Grid &grid) {
+bool Neutrals::exchange_old(Grid &grid) {
 
   std::string function = "Neutrals::exchange";
   static int iFunction = -1;