Actual source code: ex4.c
petsc-3.6.4 2016-04-12
2: static char help[] = "Tests various 2-dimensional DMDA routines.\n\n";
4: #include <petscdm.h>
5: #include <petscdmda.h>
9: int main(int argc,char **argv)
10: {
11: PetscMPIInt rank;
12: PetscErrorCode ierr;
13: PetscInt M = 10,N = 8,m = PETSC_DECIDE;
14: PetscInt s =2,w=2,n = PETSC_DECIDE,nloc,l,i,j,kk;
15: PetscInt Xs,Xm,Ys,Ym,iloc,*iglobal;
16: const PetscInt *ltog;
17: PetscInt *lx = NULL,*ly = NULL;
18: PetscBool testorder = PETSC_FALSE,flg;
19: DMBoundaryType bx = DM_BOUNDARY_NONE,by= DM_BOUNDARY_NONE;
20: DM da;
21: PetscViewer viewer;
22: Vec local,global;
23: PetscScalar value;
24: DMDAStencilType st = DMDA_STENCIL_BOX;
25: AO ao;
27: PetscInitialize(&argc,&argv,(char*)0,help);
28: PetscViewerDrawOpen(PETSC_COMM_WORLD,0,"",300,0,400,400,&viewer);
30: /* Readoptions */
31: PetscOptionsGetInt(NULL,"-NX",&M,NULL);
32: PetscOptionsGetInt(NULL,"-NY",&N,NULL);
33: PetscOptionsGetInt(NULL,"-m",&m,NULL);
34: PetscOptionsGetInt(NULL,"-n",&n,NULL);
35: PetscOptionsGetInt(NULL,"-s",&s,NULL);
36: PetscOptionsGetInt(NULL,"-w",&w,NULL);
38: flg = PETSC_FALSE;
39: PetscOptionsGetBool(NULL,"-xperiodic",&flg,NULL); if (flg) bx = DM_BOUNDARY_PERIODIC;
40: flg = PETSC_FALSE;
41: PetscOptionsGetBool(NULL,"-yperiodic",&flg,NULL); if (flg) by = DM_BOUNDARY_PERIODIC;
42: flg = PETSC_FALSE;
43: PetscOptionsGetBool(NULL,"-xghosted",&flg,NULL); if (flg) bx = DM_BOUNDARY_GHOSTED;
44: flg = PETSC_FALSE;
45: PetscOptionsGetBool(NULL,"-yghosted",&flg,NULL); if (flg) by = DM_BOUNDARY_GHOSTED;
46: flg = PETSC_FALSE;
47: PetscOptionsGetBool(NULL,"-star",&flg,NULL); if (flg) st = DMDA_STENCIL_STAR;
48: flg = PETSC_FALSE;
49: PetscOptionsGetBool(NULL,"-box",&flg,NULL); if (flg) st = DMDA_STENCIL_BOX;
50: flg = PETSC_FALSE;
51: PetscOptionsGetBool(NULL,"-testorder",&testorder,NULL);
52: /*
53: Test putting two nodes in x and y on each processor, exact last processor
54: in x and y gets the rest.
55: */
56: flg = PETSC_FALSE;
57: PetscOptionsGetBool(NULL,"-distribute",&flg,NULL);
58: if (flg) {
59: if (m == PETSC_DECIDE) SETERRQ(PETSC_COMM_WORLD,1,"Must set -m option with -distribute option");
60: PetscMalloc1(m,&lx);
61: for (i=0; i<m-1; i++) { lx[i] = 4;}
62: lx[m-1] = M - 4*(m-1);
63: if (n == PETSC_DECIDE) SETERRQ(PETSC_COMM_WORLD,1,"Must set -n option with -distribute option");
64: PetscMalloc1(n,&ly);
65: for (i=0; i<n-1; i++) { ly[i] = 2;}
66: ly[n-1] = N - 2*(n-1);
67: }
70: /* Create distributed array and get vectors */
71: DMDACreate2d(PETSC_COMM_WORLD,bx,by,st,M,N,m,n,w,s,lx,ly,&da);
72: PetscFree(lx);
73: PetscFree(ly);
75: DMView(da,viewer);
76: DMCreateGlobalVector(da,&global);
77: DMCreateLocalVector(da,&local);
79: /* Set global vector; send ghost points to local vectors */
80: value = 1;
81: VecSet(global,value);
82: DMGlobalToLocalBegin(da,global,INSERT_VALUES,local);
83: DMGlobalToLocalEnd(da,global,INSERT_VALUES,local);
85: /* Scale local vectors according to processor rank; pass to global vector */
86: MPI_Comm_rank(PETSC_COMM_WORLD,&rank);
87: value = rank;
88: VecScale(local,value);
89: DMLocalToGlobalBegin(da,local,INSERT_VALUES,global);
90: DMLocalToGlobalEnd(da,local,INSERT_VALUES,global);
92: if (!testorder) { /* turn off printing when testing ordering mappings */
93: PetscPrintf(PETSC_COMM_WORLD,"\nGlobal Vectors:\n");
94: VecView(global,PETSC_VIEWER_STDOUT_WORLD);
95: PetscPrintf(PETSC_COMM_WORLD,"\n\n");
96: }
98: /* Send ghost points to local vectors */
99: DMGlobalToLocalBegin(da,global,INSERT_VALUES,local);
100: DMGlobalToLocalEnd(da,global,INSERT_VALUES,local);
102: flg = PETSC_FALSE;
103: PetscOptionsGetBool(NULL,"-local_print",&flg,NULL);
104: if (flg) {
105: PetscViewer sviewer;
106:
107: PetscViewerASCIISynchronizedAllow(PETSC_VIEWER_STDOUT_WORLD,PETSC_TRUE);
108: PetscSynchronizedPrintf(PETSC_COMM_WORLD,"\nLocal Vector: processor %d\n",rank);
109: PetscViewerGetSingleton(PETSC_VIEWER_STDOUT_WORLD,&sviewer);
110: VecView(local,sviewer);
111: PetscViewerRestoreSingleton(PETSC_VIEWER_STDOUT_WORLD,&sviewer);
112: }
114: /* Tests mappings betweeen application/PETSc orderings */
115: if (testorder) {
116: ISLocalToGlobalMapping ltogm;
118: DMGetLocalToGlobalMapping(da,<ogm);
119: ISLocalToGlobalMappingGetSize(ltogm,&nloc);
120: ISLocalToGlobalMappingGetIndices(ltogm,<og);
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",
152: rank,j,i,l,ltog[iloc+l],iglobal[kk]);
153: }
154: kk++;
155: }
156: }
157: }
158: PetscFree(iglobal);
159: ISLocalToGlobalMappingRestoreIndices(ltogm,<og);
160: }
162: /* Free memory */
163: PetscViewerDestroy(&viewer);
164: VecDestroy(&local);
165: VecDestroy(&global);
166: DMDestroy(&da);
168: PetscFinalize();
169: return 0;
170: }