xref: /petsc/src/dm/tests/ex35.c (revision 2f613bf53f46f9356e00a2ca2bd69453be72fc31)
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   PetscErrorCode ierr;
15   DM             da;
16   PetscViewer    viewer;
17   Mat            A;
18 
19   ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
20   ierr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,"temp.dat",FILE_MODE_WRITE,&viewer);CHKERRQ(ierr);
21 
22   /* Read options */
23   ierr = PetscOptionsGetInt(NULL,NULL,"-X",&X,NULL);CHKERRQ(ierr);
24   ierr = PetscOptionsGetInt(NULL,NULL,"-Y",&Y,NULL);CHKERRQ(ierr);
25   ierr = PetscOptionsGetInt(NULL,NULL,"-Z",&Z,NULL);CHKERRQ(ierr);
26 
27   /* Create distributed array and get vectors */
28   ierr = 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);CHKERRQ(ierr);
29   ierr = DMSetFromOptions(da);CHKERRQ(ierr);
30   ierr = DMSetUp(da);CHKERRQ(ierr);
31   ierr = DMSetMatType(da,MATMPIAIJ);CHKERRQ(ierr);
32   ierr = DMCreateMatrix(da,&A);CHKERRQ(ierr);
33   ierr = MatShift(A,X);CHKERRQ(ierr);
34   ierr = MatView(A,viewer);CHKERRQ(ierr);
35   ierr = MatDestroy(&A);CHKERRQ(ierr);
36   ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
37 
38   ierr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,"temp.dat",FILE_MODE_READ,&viewer);CHKERRQ(ierr);
39   ierr = DMCreateMatrix(da,&A);CHKERRQ(ierr);
40   ierr = MatLoad(A,viewer);CHKERRQ(ierr);
41 
42   /* Free memory */
43   ierr = MatDestroy(&A);CHKERRQ(ierr);
44   ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
45   ierr = DMDestroy(&da);CHKERRQ(ierr);
46   ierr = PetscFinalize();
47   return ierr;
48 }
49