Actual source code: ex4.c

  1: /*$Id: ex4.c,v 1.53 2001/08/07 03:04:42 balay Exp $*/
  2: 
  3: static char help[] = "Tests various 2-dimensional DA routines.nn";

 5:  #include petscda.h
 6:  #include petscsys.h

  8: int main(int argc,char **argv)
  9: {
 10:   int            rank,M = 10,N = 8,m = PETSC_DECIDE,ierr;
 11:   int            s=2,w=2,n = PETSC_DECIDE,nloc,l,i,j,kk;
 12:   int            Xs,Xm,Ys,Ym,iloc,*iglobal,*ltog;
 13:   int            *lx = PETSC_NULL,*ly = PETSC_NULL;
 14:   PetscTruth     testorder,flg;
 15:   DAPeriodicType wrap = DA_NONPERIODIC;
 16:   DA             da;
 17:   PetscViewer    viewer;
 18:   Vec            local,global;
 19:   PetscScalar    value;
 20:   DAStencilType  st = DA_STENCIL_BOX;
 21:   AO             ao;
 22: 
 23:   PetscInitialize(&argc,&argv,(char*)0,help);
 24:   PetscViewerDrawOpen(PETSC_COMM_WORLD,0,"",300,0,400,400,&viewer);
 25: 
 26:   /* Readoptions */
 27:   PetscOptionsGetInt(PETSC_NULL,"-M",&M,PETSC_NULL);
 28:   PetscOptionsGetInt(PETSC_NULL,"-N",&N,PETSC_NULL);
 29:   PetscOptionsGetInt(PETSC_NULL,"-m",&m,PETSC_NULL);
 30:   PetscOptionsGetInt(PETSC_NULL,"-n",&n,PETSC_NULL);
 31:   PetscOptionsGetInt(PETSC_NULL,"-s",&s,PETSC_NULL);
 32:   PetscOptionsGetInt(PETSC_NULL,"-w",&w,PETSC_NULL);
 33:   PetscOptionsHasName(PETSC_NULL,"-xwrap",&flg); if (flg)  wrap = DA_XPERIODIC;
 34:   PetscOptionsHasName(PETSC_NULL,"-ywrap",&flg); if (flg)  wrap = DA_YPERIODIC;
 35:   PetscOptionsHasName(PETSC_NULL,"-xywrap",&flg); if (flg) wrap = DA_XYPERIODIC;
 36:   PetscOptionsHasName(PETSC_NULL,"-star",&flg); if (flg)   st = DA_STENCIL_STAR;
 37:   PetscOptionsHasName(PETSC_NULL,"-testorder",&testorder);
 38:   /*
 39:       Test putting two nodes in x and y on each processor, exact last processor 
 40:       in x and y gets the rest.
 41:   */
 42:   PetscOptionsHasName(PETSC_NULL,"-distribute",&flg);
 43:   if (flg) {
 44:     if (m == PETSC_DECIDE) SETERRQ(1,"Must set -m option with -distribute option");
 45:     PetscMalloc(m*sizeof(int),&lx);
 46:     for (i=0; i<m-1; i++) { lx[i] = 4;}
 47:     lx[m-1] = M - 4*(m-1);
 48:     if (n == PETSC_DECIDE) SETERRQ(1,"Must set -n option with -distribute option");
 49:     PetscMalloc(n*sizeof(int),&ly);
 50:     for (i=0; i<n-1; i++) { ly[i] = 2;}
 51:     ly[n-1] = N - 2*(n-1);
 52:   }


 55:   /* Create distributed array and get vectors */
 56:   DACreate2d(PETSC_COMM_WORLD,wrap,st,M,N,m,n,w,s,lx,ly,&da);
 57:   if (lx) {
 58:     PetscFree(lx);
 59:     PetscFree(ly);
 60:   }

 62:   DAView(da,viewer);
 63:   DACreateGlobalVector(da,&global);
 64:   DACreateLocalVector(da,&local);

 66:   /* Set global vector; send ghost points to local vectors */
 67:   value = 1;
 68:   VecSet(&value,global);
 69:   DAGlobalToLocalBegin(da,global,INSERT_VALUES,local);
 70:   DAGlobalToLocalEnd(da,global,INSERT_VALUES,local);

 72:   /* Scale local vectors according to processor rank; pass to global vector */
 73:   MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
 74:   value = rank;
 75:   VecScale(&value,local);
 76:   DALocalToGlobal(da,local,INSERT_VALUES,global);

 78:   if (!testorder) { /* turn off printing when testing ordering mappings */
 79:     PetscPrintf (PETSC_COMM_WORLD,"nGlobal Vectors:n");
 80:     PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_NATIVE);
 81:     VecView(global,PETSC_VIEWER_STDOUT_WORLD);
 82:     PetscPrintf (PETSC_COMM_WORLD,"nn");
 83:   }

 85:   /* Send ghost points to local vectors */
 86:   DAGlobalToLocalBegin(da,global,INSERT_VALUES,local);
 87:   DAGlobalToLocalEnd(da,global,INSERT_VALUES,local);

 89:   PetscOptionsHasName(PETSC_NULL,"-local_print",&flg);
 90:   if (flg) {
 91:     PetscViewer sviewer;
 92:     PetscSynchronizedPrintf(PETSC_COMM_WORLD,"nLocal Vector: processor %dn",rank);
 93:     PetscViewerGetSingleton(PETSC_VIEWER_STDOUT_WORLD,&sviewer);
 94:     VecView(local,sviewer);
 95:     PetscViewerRestoreSingleton(PETSC_VIEWER_STDOUT_WORLD,&sviewer);
 96:   }

 98:   /* Tests mappings betweeen application/PETSc orderings */
 99:   if (testorder) {
100:     DAGetGhostCorners(da,&Xs,&Ys,PETSC_NULL,&Xm,&Ym,PETSC_NULL);
101:     DAGetGlobalIndices(da,&nloc,&ltog);
102:     DAGetAO(da,&ao);
103:     PetscMalloc(nloc*sizeof(int),&iglobal);

105:     /* Set iglobal to be global indices for each processor's local and ghost nodes,
106:        using the DA ordering of grid points */
107:     kk = 0;
108:     for (j=Ys; j<Ys+Ym; j++) {
109:       for (i=Xs; i<Xs+Xm; i++) {
110:         iloc = w*((j-Ys)*Xm + i-Xs);
111:         for (l=0; l<w; l++) {
112:           iglobal[kk++] = ltog[iloc+l];
113:         }
114:       }
115:     }

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

121:     /* Then map the application ordering back to the PETSc DA ordering */
122:     AOApplicationToPetsc(ao,nloc,iglobal);

124:     /* Verify the mappings */
125:     kk=0;
126:     for (j=Ys; j<Ys+Ym; j++) {
127:       for (i=Xs; i<Xs+Xm; i++) {
128:         iloc = w*((j-Ys)*Xm + i-Xs);
129:         for (l=0; l<w; l++) {
130:           if (iglobal[kk] != ltog[iloc+l]) {fprintf(stdout,
131:             "[%d] Problem with mapping: j=%d, i=%d, l=%d, petsc1=%d, petsc2=%dn",
132:              rank,j,i,l,ltog[iloc+l],iglobal[kk]);}
133:           kk++;
134:         }
135:       }
136:     }
137:     PetscFree(iglobal);
138:   }

140:   /* Free memory */
141:   PetscViewerDestroy(viewer);
142:   VecDestroy(local);
143:   VecDestroy(global);
144:   DADestroy(da);

146:   PetscFinalize();
147:   return 0;
148: }