Actual source code: ex4.c


  2: static char help[] = "Tests various 2-dimensional DMDA routines.\n\n";

  4: #include <petscdm.h>
  5: #include <petscdmda.h>

  7: int main(int argc,char **argv)
  8: {
  9:   PetscMPIInt      rank;
 10:   PetscErrorCode   ierr;
 11:   PetscInt         M = 10,N = 8,m = PETSC_DECIDE;
 12:   PetscInt         s =2,w=2,n = PETSC_DECIDE,nloc,l,i,j,kk;
 13:   PetscInt         Xs,Xm,Ys,Ym,iloc,*iglobal;
 14:   const PetscInt   *ltog;
 15:   PetscInt         *lx       = NULL,*ly = NULL;
 16:   PetscBool        testorder = PETSC_FALSE,flg;
 17:   DMBoundaryType   bx        = DM_BOUNDARY_NONE,by= DM_BOUNDARY_NONE;
 18:   DM               da;
 19:   PetscViewer      viewer;
 20:   Vec              local,global;
 21:   PetscScalar      value;
 22:   DMDAStencilType  st = DMDA_STENCIL_BOX;
 23:   AO               ao;

 25:   PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
 26:   PetscViewerDrawOpen(PETSC_COMM_WORLD,0,"",300,0,400,400,&viewer);

 28:   /* Readoptions */
 29:   PetscOptionsGetInt(NULL,NULL,"-NX",&M,NULL);
 30:   PetscOptionsGetInt(NULL,NULL,"-NY",&N,NULL);
 31:   PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL);
 32:   PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
 33:   PetscOptionsGetInt(NULL,NULL,"-s",&s,NULL);
 34:   PetscOptionsGetInt(NULL,NULL,"-w",&w,NULL);

 36:   flg  = PETSC_FALSE;
 37:   PetscOptionsGetBool(NULL,NULL,"-xperiodic",&flg,NULL); if (flg) bx = DM_BOUNDARY_PERIODIC;
 38:   flg  = PETSC_FALSE;
 39:   PetscOptionsGetBool(NULL,NULL,"-yperiodic",&flg,NULL); if (flg) by = DM_BOUNDARY_PERIODIC;
 40:   flg  = PETSC_FALSE;
 41:   PetscOptionsGetBool(NULL,NULL,"-xghosted",&flg,NULL); if (flg) bx = DM_BOUNDARY_GHOSTED;
 42:   flg  = PETSC_FALSE;
 43:   PetscOptionsGetBool(NULL,NULL,"-yghosted",&flg,NULL); if (flg) by = DM_BOUNDARY_GHOSTED;
 44:   flg  = PETSC_FALSE;
 45:   PetscOptionsGetBool(NULL,NULL,"-star",&flg,NULL); if (flg) st = DMDA_STENCIL_STAR;
 46:   flg  = PETSC_FALSE;
 47:   PetscOptionsGetBool(NULL,NULL,"-box",&flg,NULL); if (flg) st = DMDA_STENCIL_BOX;
 48:   flg  = PETSC_FALSE;
 49:   PetscOptionsGetBool(NULL,NULL,"-testorder",&testorder,NULL);
 50:   /*
 51:       Test putting two nodes in x and y on each processor, exact last processor
 52:       in x and y gets the rest.
 53:   */
 54:   flg  = PETSC_FALSE;
 55:   PetscOptionsGetBool(NULL,NULL,"-distribute",&flg,NULL);
 56:   if (flg) {
 57:     if (m == PETSC_DECIDE) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_USER_INPUT,"Must set -m option with -distribute option");
 58:     PetscMalloc1(m,&lx);
 59:     for (i=0; i<m-1; i++) { lx[i] = 4;}
 60:     lx[m-1] = M - 4*(m-1);
 61:     if (n == PETSC_DECIDE) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_USER_INPUT,"Must set -n option with -distribute option");
 62:     PetscMalloc1(n,&ly);
 63:     for (i=0; i<n-1; i++) { ly[i] = 2;}
 64:     ly[n-1] = N - 2*(n-1);
 65:   }

 67:   /* Create distributed array and get vectors */
 68:   DMDACreate2d(PETSC_COMM_WORLD,bx,by,st,M,N,m,n,w,s,lx,ly,&da);
 69:   DMSetFromOptions(da);
 70:   DMSetUp(da);
 71:   PetscFree(lx);
 72:   PetscFree(ly);

 74:   DMView(da,viewer);
 75:   DMCreateGlobalVector(da,&global);
 76:   DMCreateLocalVector(da,&local);

 78:   /* Set global vector; send ghost points to local vectors */
 79:   value = 1;
 80:   VecSet(global,value);
 81:   DMGlobalToLocalBegin(da,global,INSERT_VALUES,local);
 82:   DMGlobalToLocalEnd(da,global,INSERT_VALUES,local);

 84:   /* Scale local vectors according to processor rank; pass to global vector */
 85:   MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
 86:   value = rank;
 87:   VecScale(local,value);
 88:   DMLocalToGlobalBegin(da,local,INSERT_VALUES,global);
 89:   DMLocalToGlobalEnd(da,local,INSERT_VALUES,global);

 91:   if (!testorder) { /* turn off printing when testing ordering mappings */
 92:     PetscPrintf(PETSC_COMM_WORLD,"\nGlobal Vectors:\n");
 93:     VecView(global,PETSC_VIEWER_STDOUT_WORLD);
 94:     PetscPrintf(PETSC_COMM_WORLD,"\n\n");
 95:   }

 97:   /* Send ghost points to local vectors */
 98:   DMGlobalToLocalBegin(da,global,INSERT_VALUES,local);
 99:   DMGlobalToLocalEnd(da,global,INSERT_VALUES,local);

101:   flg  = PETSC_FALSE;
102:   PetscOptionsGetBool(NULL,NULL,"-local_print",&flg,NULL);
103:   if (flg) {
104:     PetscViewer sviewer;

106:     PetscViewerASCIIPushSynchronized(PETSC_VIEWER_STDOUT_WORLD);
107:     PetscSynchronizedPrintf(PETSC_COMM_WORLD,"\nLocal Vector: processor %d\n",rank);
108:     PetscViewerGetSubViewer(PETSC_VIEWER_STDOUT_WORLD,PETSC_COMM_SELF,&sviewer);
109:     VecView(local,sviewer);
110:     PetscViewerRestoreSubViewer(PETSC_VIEWER_STDOUT_WORLD,PETSC_COMM_SELF,&sviewer);
111:     PetscViewerFlush(PETSC_VIEWER_STDOUT_WORLD);
112:     PetscViewerASCIIPopSynchronized(PETSC_VIEWER_STDOUT_WORLD);
113:   }

115:   /* Tests mappings between application/PETSc orderings */
116:   if (testorder) {
117:     ISLocalToGlobalMapping ltogm;

119:     DMGetLocalToGlobalMapping(da,&ltogm);
120:     ISLocalToGlobalMappingGetSize(ltogm,&nloc);
121:     ISLocalToGlobalMappingGetIndices(ltogm,&ltog);
122:     DMDAGetGhostCorners(da,&Xs,&Ys,NULL,&Xm,&Ym,NULL);
123:     DMDAGetAO(da,&ao);
124:     PetscMalloc1(nloc,&iglobal);

126:     /* Set iglobal to be global indices for each processor's local and ghost nodes,
127:        using the DMDA ordering of grid points */
128:     kk = 0;
129:     for (j=Ys; j<Ys+Ym; j++) {
130:       for (i=Xs; i<Xs+Xm; i++) {
131:         iloc = w*((j-Ys)*Xm + i-Xs);
132:         for (l=0; l<w; l++) {
133:           iglobal[kk++] = ltog[iloc+l];
134:         }
135:       }
136:     }

138:     /* Map this to the application ordering (which for DMDAs is just the natural ordering
139:        that would be used for 1 processor, numbering most rapidly by x, then y) */
140:     AOPetscToApplication(ao,nloc,iglobal);

142:     /* Then map the application ordering back to the PETSc DMDA ordering */
143:     AOApplicationToPetsc(ao,nloc,iglobal);

145:     /* Verify the mappings */
146:     kk=0;
147:     for (j=Ys; j<Ys+Ym; j++) {
148:       for (i=Xs; i<Xs+Xm; i++) {
149:         iloc = w*((j-Ys)*Xm + i-Xs);
150:         for (l=0; l<w; l++) {
151:           if (iglobal[kk] != ltog[iloc+l]) {
152:             PetscFPrintf(PETSC_COMM_SELF,stdout,"[%d] Problem with mapping: j=%D, i=%D, l=%D, petsc1=%D, petsc2=%D\n",rank,j,i,l,ltog[iloc+l],iglobal[kk]);
153:           }
154:           kk++;
155:         }
156:       }
157:     }
158:     PetscFree(iglobal);
159:     ISLocalToGlobalMappingRestoreIndices(ltogm,&ltog);
160:   }

162:   /* Free memory */
163:   PetscViewerDestroy(&viewer);
164:   VecDestroy(&local);
165:   VecDestroy(&global);
166:   DMDestroy(&da);

168:   PetscFinalize();
169:   return ierr;
170: }

172: /*TEST

174:    test:
175:       nsize: 4
176:       args: -nox
177:       filter: grep -v -i Object
178:       requires: x

180:    test:
181:       suffix: 2
182:       args: -testorder -nox
183:       requires: x

185: TEST*/