1 2 static char help[] = "MatLoad test for loading matrices that are created by DMCreateMatrix() and\n\ 3 stored in binary via MatView_MPI_DA.MatView_MPI_DA stores the matrix\n\ 4 in natural ordering. Hence MatLoad() has to read the matrix first in\n\ 5 natural ordering and then permute it back to the application ordering.This\n\ 6 example is used for testing the subroutine MatLoad_MPI_DA\n\n"; 7 8 #include <petscdm.h> 9 #include <petscdmda.h> 10 11 int main(int argc, char **argv) 12 { 13 PetscInt X = 10, Y = 8, Z = 8; 14 DM da; 15 PetscViewer viewer; 16 Mat A; 17 18 PetscFunctionBeginUser; 19 PetscCall(PetscInitialize(&argc, &argv, (char *)0, help)); 20 PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD, "temp.dat", FILE_MODE_WRITE, &viewer)); 21 22 /* Read options */ 23 PetscCall(PetscOptionsGetInt(NULL, NULL, "-X", &X, NULL)); 24 PetscCall(PetscOptionsGetInt(NULL, NULL, "-Y", &Y, NULL)); 25 PetscCall(PetscOptionsGetInt(NULL, NULL, "-Z", &Z, NULL)); 26 27 /* Create distributed array and get vectors */ 28 PetscCall(DMDACreate3d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DMDA_STENCIL_STAR, X, Y, Z, PETSC_DECIDE, PETSC_DECIDE, PETSC_DECIDE, 1, 1, NULL, NULL, NULL, &da)); 29 PetscCall(DMSetFromOptions(da)); 30 PetscCall(DMSetUp(da)); 31 PetscCall(DMSetMatType(da, MATMPIAIJ)); 32 PetscCall(DMCreateMatrix(da, &A)); 33 PetscCall(MatShift(A, X)); 34 PetscCall(MatView(A, viewer)); 35 PetscCall(MatDestroy(&A)); 36 PetscCall(PetscViewerDestroy(&viewer)); 37 38 PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD, "temp.dat", FILE_MODE_READ, &viewer)); 39 PetscCall(DMCreateMatrix(da, &A)); 40 PetscCall(MatLoad(A, viewer)); 41 42 /* Free memory */ 43 PetscCall(MatDestroy(&A)); 44 PetscCall(PetscViewerDestroy(&viewer)); 45 PetscCall(DMDestroy(&da)); 46 PetscCall(PetscFinalize()); 47 return 0; 48 } 49