210   PetscMPIInt   n_neigh;  in PCNNCreateCoarseMatrix()  local
214   PetscCall(PetscMPIIntCast(pcis->n_neigh, &n_neigh));  in PCNNCreateCoarseMatrix()
216   PetscCall(PetscMalloc1(n_neigh * n_neigh + 1, &mat));  in PCNNCreateCoarseMatrix()
223     PetscCall(PetscMalloc((n_neigh + 1) * sizeof(PetscScalar *), &pcnn->DZ_IN));  in PCNNCreateCoarseMatrix()
225     PetscCall(PetscMalloc((n_neigh + 1) * sizeof(PetscScalar *), &DZ_OUT));  in PCNNCreateCoarseMatrix()
226     for (i = 0; i < n_neigh; i++) size_of_Z += n_shared[i];  in PCNNCreateCoarseMatrix()
230   for (i = 1; i < n_neigh; i++) {  in PCNNCreateCoarseMatrix()
238   for (i = 1; i < n_neigh; i++) {  in PCNNCreateCoarseMatrix()
248     PetscCall(PetscMalloc2(n_neigh + 1, &send_request, n_neigh + 1, &recv_request));  in PCNNCreateCoarseMatrix()
249     for (i = 1; i < n_neigh; i++) {  in PCNNCreateCoarseMatrix()
268   for (i = 0; i < n_neigh; i++) {  in PCNNCreateCoarseMatrix()
272       PetscCallMPI(MPI_Waitany(n_neigh - 1, recv_request + 1, &ind, &stat));  in PCNNCreateCoarseMatrix()
275     mat[ind * n_neigh + 0] = 0.0;  in PCNNCreateCoarseMatrix()
276 …for (k = 0; k < n_shared[ind]; k++) mat[ind * n_neigh + 0] += DZ_IN[ind][k] * pcis->work_N[shared[…  in PCNNCreateCoarseMatrix()
280   for (j = 1; j < n_neigh; j++) {  in PCNNCreateCoarseMatrix()
282     for (i = 0; i < n_neigh; i++) {  in PCNNCreateCoarseMatrix()
283       mat[i * n_neigh + j] = 0.0;  in PCNNCreateCoarseMatrix()
284 …for (k = 0; k < n_shared[i]; k++) mat[i * n_neigh + j] += DZ_IN[i][k] * pcis->work_N[shared[i][k]];  in PCNNCreateCoarseMatrix()
289   if (n_neigh > 1) {  in PCNNCreateCoarseMatrix()
291     PetscCall(PetscMalloc1(n_neigh - 1, &stat));  in PCNNCreateCoarseMatrix()
292     if (n_neigh - 1) PetscCallMPI(MPI_Waitall(n_neigh - 1, &send_request[1], stat));  in PCNNCreateCoarseMatrix()
316     PetscCall(MatMPIAIJSetPreallocation(pcnn->coarse_mat, 1, NULL, n_neigh, NULL));  in PCNNCreateCoarseMatrix()
319     PetscCall(MatSetValues(pcnn->coarse_mat, n_neigh, neigh, n_neigh, neigh, mat, ADD_VALUES));  in PCNNCreateCoarseMatrix()