Actual source code: ex11.c

petsc-3.3-p6 2013-02-11
  2: static char help[] = "Tests various 2-dimensional DM routines.\n\n";

  4: #include <petscdmda.h>

  8: int main(int argc,char **argv)
  9: {
 10:   PetscInt       M = 5,N = 4,dof=1,s=1,bx=0,by=0,i,n,j,k,m,cnt;
 12:   DM             da;
 13:   PetscViewer    viewer;
 14:   Vec            local,locala,global,coors;
 15:   PetscScalar    *xy,*alocal;
 16:   PetscDraw      draw;
 17:   char           fname[16];

 19:   PetscInitialize(&argc,&argv,(char*)0,help);

 21:   /* Create viewers */
 22:   PetscViewerDrawOpen(PETSC_COMM_WORLD,0,"",PETSC_DECIDE,PETSC_DECIDE,600,200,&viewer);
 23:   PetscViewerDrawGetDraw(viewer,0,&draw);
 24:   PetscDrawSetDoubleBuffer(draw);

 26:   /* Read options */
 27:   PetscOptionsGetInt(PETSC_NULL,"-M",&M,PETSC_NULL);
 28:   PetscOptionsGetInt(PETSC_NULL,"-N",&N,PETSC_NULL);
 29:   PetscOptionsGetInt(PETSC_NULL,"-dof",&dof,PETSC_NULL);
 30:   PetscOptionsGetInt(PETSC_NULL,"-s",&s,PETSC_NULL);
 31:   PetscOptionsGetInt(PETSC_NULL,"-periodic_x",&wrap,PETSC_NULL);
 32:   PetscOptionsGetInt(PETSC_NULL,"-periodic_y",&wrap,PETSC_NULL);

 34:   /* Create distributed array and get vectors */
 35:   DMDACreate2d(PETSC_COMM_WORLD,(DMDABoundaryType)bx,(DMDABoundaryType)by,DMDA_STENCIL_BOX,M,N,PETSC_DECIDE,
 36:                     PETSC_DECIDE,dof,s,PETSC_NULL,PETSC_NULL,&da);
 37:   DMDASetUniformCoordinates(da,0.0,1.0,0.0,1.0,0.0,0.0);
 38:   for (i=0; i<dof; i++) {
 39:     sprintf(fname,"Field %d",(int)i);
 40:     DMDASetFieldName(da,i,fname);
 41:   }

 43:   DMView(da,viewer);
 44:   DMCreateGlobalVector(da,&global);
 45:   DMCreateLocalVector(da,&local);
 46:   DMCreateLocalVector(da,&locala);
 47:   DMDAGetCoordinates(da,&coors);
 48:   VecGetArray(coors,&xy);

 50:   VecView(coors,PETSC_VIEWER_STDOUT_SELF);

 52:   /* Set values into local vectors */
 53:   VecGetArray(local,&alocal);
 54:   DMDAGetGhostCorners(da,0,0,0,&m,&n,0);
 55:   n    = n/dof;
 56:   for (k=0; k<dof; k++) {
 57:     cnt = 0;
 58:     for (j=0; j<n; j++) {
 59:       for (i=0; i<m; i++) {
 60:         alocal[k+dof*cnt] = PetscSinScalar(2.0*PETSC_PI*(k+1)*xy[2*cnt]);
 61:         cnt++;
 62:       }
 63:     }
 64:   }
 65:   VecRestoreArray(local,&alocal);
 66:   VecRestoreArray(coors,&xy);

 68:   DMLocalToGlobalBegin(da,local,INSERT_VALUES,global);
 69:   DMLocalToGlobalEnd(da,local,INSERT_VALUES,global);

 71:   VecView(global,viewer);

 73:   /* Send ghost points to local vectors */
 74:   DMGlobalToLocalBegin(da,global,INSERT_VALUES,locala);
 75:   DMGlobalToLocalEnd(da,global,INSERT_VALUES,locala);

 77:   /* Free memory */
 78:   PetscViewerDestroy(&viewer);
 79:   VecDestroy(&global);
 80:   VecDestroy(&local);
 81:   VecDestroy(&locala);
 82:   DMDestroy(&da);
 83:   PetscFinalize();
 84:   return 0;
 85: }
 86: