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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

144:     /* Verify the mappings */
145:     kk=0;
146:     for (j=Ys; j<Ys+Ym; j++) {
147:       for (i=Xs; i<Xs+Xm; i++) {
148:         iloc = w*((j-Ys)*Xm + i-Xs);
149:         for (l=0; l<w; l++) {
150:           if (iglobal[kk] != ltog[iloc+l]) {
151:             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]);
152:           }
153:           kk++;
154:         }
155:       }
156:     }
157:     PetscFree(iglobal);
158:     ISLocalToGlobalMappingRestoreIndices(ltogm,&ltog);
159:   }

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

167:   PetscFinalize();
168:   return 0;
169: }

171: /*TEST

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

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

184: TEST*/