diff --git a/BasicSolver/2D-mpi/src/comm-v2.c b/BasicSolver/2D-mpi/src/comm-v2.c
index 4e53e33..7b4e60f 100644
--- a/BasicSolver/2D-mpi/src/comm-v2.c
+++ b/BasicSolver/2D-mpi/src/comm-v2.c
@@ -252,15 +252,18 @@ void commPartition(Comm* c, int jmax, int imax)
     MPI_Cart_shift(c->comm, JDIM, 1, &c->neighbours[BOTTOM], &c->neighbours[TOP]);
     MPI_Cart_get(c->comm, NDIMS, c->dims, periods, c->coords);
 
-    c->imaxLocal = sizeOfRank(c->rank, dims[IDIM], imax);
-    c->jmaxLocal = sizeOfRank(c->rank, dims[JDIM], jmax);
+    int imaxLocal = sizeOfRank(c->rank, dims[IDIM], imax);
+    int jmaxLocal = sizeOfRank(c->rank, dims[JDIM], jmax);
+
+    c->imaxLocal = imaxLocal;
+    c->jmaxLocal = jmaxLocal;
 
     MPI_Datatype jBufferType;
-    MPI_Type_contiguous(c->imaxLocal, MPI_DOUBLE, &jBufferType);
+    MPI_Type_contiguous(imaxLocal, MPI_DOUBLE, &jBufferType);
     MPI_Type_commit(&jBufferType);
 
     MPI_Datatype iBufferType;
-    MPI_Type_vector(c->jmaxLocal, 1, c->imaxLocal + 2, MPI_DOUBLE, &iBufferType);
+    MPI_Type_vector(jmaxLocal, 1, imaxLocal + 2, MPI_DOUBLE, &iBufferType);
     MPI_Type_commit(&iBufferType);
 
     c->bufferTypes[LEFT]   = iBufferType;
@@ -268,14 +271,15 @@ void commPartition(Comm* c, int jmax, int imax)
     c->bufferTypes[BOTTOM] = jBufferType;
     c->bufferTypes[TOP]    = jBufferType;
 
-    c->rdispls[LEFT]   = (c->imaxLocal + 2);
-    c->rdispls[RIGHT]  = (c->imaxLocal + 2) + (c->imaxLocal + 1);
+    c->sdispls[LEFT]   = (imaxLocal + 2) + 1;
+    c->sdispls[RIGHT]  = (imaxLocal + 2) + imaxLocal;
+    c->sdispls[BOTTOM] = (imaxLocal + 2) + 1;
+    c->sdispls[TOP]    = jmaxLocal * (imaxLocal + 2) + 1;
+
+    c->rdispls[LEFT]   = (imaxLocal + 2);
+    c->rdispls[RIGHT]  = (imaxLocal + 2) + (imaxLocal + 1);
     c->rdispls[BOTTOM] = 1;
-    c->rdispls[TOP]    = (c->jmaxLocal + 1) * (c->imaxLocal + 2) + 1;
-    c->sdispls[LEFT]   = (c->imaxLocal + 2) + 1;
-    c->sdispls[RIGHT]  = (c->imaxLocal + 2) + (c->imaxLocal);
-    c->sdispls[BOTTOM] = (c->imaxLocal + 2) + 1;
-    c->sdispls[TOP]    = (c->jmaxLocal) * (c->imaxLocal + 2) + 1;
+    c->rdispls[TOP]    = (jmaxLocal + 1) * (imaxLocal + 2) + 1;
 #else
     c->imaxLocal = imax;
     c->jmaxLocal = jmax;
diff --git a/BasicSolver/2D-mpi/src/comm-v3.c b/BasicSolver/2D-mpi/src/comm-v3.c
index c8bd0b5..e47c10e 100644
--- a/BasicSolver/2D-mpi/src/comm-v3.c
+++ b/BasicSolver/2D-mpi/src/comm-v3.c
@@ -4,7 +4,6 @@
  * Use of this source code is governed by a MIT style
  * license that can be found in the LICENSE file.
  */
-#include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
 
@@ -234,27 +233,26 @@ void commPartition(Comm* c, int jmax, int imax)
     MPI_Cart_shift(c->comm, JDIM, 1, &c->neighbours[BOTTOM], &c->neighbours[TOP]);
     MPI_Cart_get(c->comm, NDIMS, c->dims, periods, c->coords);
 
-    c->imaxLocal = sizeOfRank(c->rank, dims[IDIM], imax);
-    c->jmaxLocal = sizeOfRank(c->rank, dims[JDIM], jmax);
+    int imaxLocal = sizeOfRank(c->rank, dims[IDIM], imax);
+    int jmaxLocal = sizeOfRank(c->rank, dims[JDIM], jmax);
+
+    c->imaxLocal = imaxLocal;
+    c->jmaxLocal = jmaxLocal;
 
     MPI_Datatype jBufferType;
-    MPI_Type_contiguous(c->imaxLocal, MPI_DOUBLE, &jBufferType);
+    MPI_Type_contiguous(imaxLocal, MPI_DOUBLE, &jBufferType);
     MPI_Type_commit(&jBufferType);
 
     MPI_Datatype iBufferType;
-    MPI_Type_vector(c->jmaxLocal, 1, c->imaxLocal + 2, MPI_DOUBLE, &iBufferType);
+    MPI_Type_vector(jmaxLocal, 1, imaxLocal + 2, MPI_DOUBLE, &iBufferType);
     MPI_Type_commit(&iBufferType);
 
-    // in the order of the dimensions i->0, j->1
-    // first negative direction, then positive direction
-    size_t dblsize         = sizeof(double);
-    int imaxLocal          = c->imaxLocal;
-    int jmaxLocal          = c->jmaxLocal;
     c->bufferTypes[LEFT]   = iBufferType;
     c->bufferTypes[RIGHT]  = iBufferType;
     c->bufferTypes[BOTTOM] = jBufferType;
     c->bufferTypes[TOP]    = jBufferType;
 
+    size_t dblsize     = sizeof(double);
     c->sdispls[LEFT]   = ((imaxLocal + 2) + 1) * dblsize;             // send left
     c->sdispls[RIGHT]  = ((imaxLocal + 2) + imaxLocal) * dblsize;     // send right
     c->sdispls[BOTTOM] = ((imaxLocal + 2) + 1) * dblsize;             // send bottom