xref: /petsc/src/dm/tests/ex7.c (revision 8fb5bd83c3955fefcf33a54e3bb66920a9fa884b)
1 
2 static char help[] = "Tests DMLocalToLocalxxx() for DMDA.\n\n";
3 
4 #include <petscdmda.h>
5 
6 int main(int argc,char **argv)
7 {
8   PetscMPIInt      rank;
9   PetscInt         M=8,dof=1,stencil_width=1,i,start,end,P=5,N = 6,m=PETSC_DECIDE,n=PETSC_DECIDE,p=PETSC_DECIDE,pt = 0,st = 0;
10   PetscBool        flg = PETSC_FALSE,flg2,flg3;
11   DMBoundaryType   periodic;
12   DMDAStencilType  stencil_type;
13   DM               da;
14   Vec              local,global,local_copy;
15   PetscScalar      value;
16   PetscReal        norm,work;
17   PetscViewer      viewer;
18   char             filename[64];
19   FILE             *file;
20 
21   PetscCall(PetscInitialize(&argc,&argv,(char*)0,help));
22   PetscCall(PetscOptionsGetInt(NULL,NULL,"-M",&M,NULL));
23   PetscCall(PetscOptionsGetInt(NULL,NULL,"-N",&N,NULL));
24   PetscCall(PetscOptionsGetInt(NULL,NULL,"-dof",&dof,NULL));
25   PetscCall(PetscOptionsGetInt(NULL,NULL,"-stencil_width",&stencil_width,NULL));
26   PetscCall(PetscOptionsGetInt(NULL,NULL,"-periodic",&pt,NULL));
27 
28   periodic = (DMBoundaryType) pt;
29 
30   PetscCall(PetscOptionsGetInt(NULL,NULL,"-stencil_type",&st,NULL));
31 
32   stencil_type = (DMDAStencilType) st;
33 
34   PetscCall(PetscOptionsHasName(NULL,NULL,"-grid2d",&flg2));
35   PetscCall(PetscOptionsHasName(NULL,NULL,"-grid3d",&flg3));
36   if (flg2) {
37     PetscCall(DMDACreate2d(PETSC_COMM_WORLD,periodic,periodic,stencil_type,M,N,m,n,dof,stencil_width,NULL,NULL,&da));
38   } else if (flg3) {
39     PetscCall(DMDACreate3d(PETSC_COMM_WORLD,periodic,periodic,periodic,stencil_type,M,N,P,m,n,p,dof,stencil_width,NULL,NULL,NULL,&da));
40   } else {
41     PetscCall(DMDACreate1d(PETSC_COMM_WORLD,periodic,M,dof,stencil_width,NULL,&da));
42   }
43   PetscCall(DMSetFromOptions(da));
44   PetscCall(DMSetUp(da));
45 
46   PetscCall(DMCreateGlobalVector(da,&global));
47   PetscCall(DMCreateLocalVector(da,&local));
48   PetscCall(VecDuplicate(local,&local_copy));
49 
50   /* zero out vectors so that ghostpoints are zero */
51   value = 0;
52   PetscCall(VecSet(local,value));
53   PetscCall(VecSet(local_copy,value));
54 
55   PetscCall(VecGetOwnershipRange(global,&start,&end));
56   for (i=start; i<end; i++) {
57     value = i + 1;
58     PetscCall(VecSetValues(global,1,&i,&value,INSERT_VALUES));
59   }
60   PetscCall(VecAssemblyBegin(global));
61   PetscCall(VecAssemblyEnd(global));
62 
63   PetscCall(DMGlobalToLocalBegin(da,global,INSERT_VALUES,local));
64   PetscCall(DMGlobalToLocalEnd(da,global,INSERT_VALUES,local));
65 
66   PetscCall(DMLocalToLocalBegin(da,local,INSERT_VALUES,local_copy));
67   PetscCall(DMLocalToLocalEnd(da,local,INSERT_VALUES,local_copy));
68 
69   PetscCall(PetscOptionsGetBool(NULL,NULL,"-save",&flg,NULL));
70   if (flg) {
71     PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank));
72     sprintf(filename,"local.%d",rank);
73     PetscCall(PetscViewerASCIIOpen(PETSC_COMM_SELF,filename,&viewer));
74     PetscCall(PetscViewerASCIIGetPointer(viewer,&file));
75     PetscCall(VecView(local,viewer));
76     fprintf(file,"Vector with correct ghost points\n");
77     PetscCall(VecView(local_copy,viewer));
78     PetscCall(PetscViewerDestroy(&viewer));
79   }
80 
81   PetscCall(VecAXPY(local_copy,-1.0,local));
82   PetscCall(VecNorm(local_copy,NORM_MAX,&work));
83   PetscCallMPI(MPI_Allreduce(&work,&norm,1,MPIU_REAL,MPIU_MAX,PETSC_COMM_WORLD));
84   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Norm of difference %g should be zero\n",(double)norm));
85 
86   PetscCall(VecDestroy(&local_copy));
87   PetscCall(VecDestroy(&local));
88   PetscCall(VecDestroy(&global));
89   PetscCall(DMDestroy(&da));
90   PetscCall(PetscFinalize());
91   return 0;
92 }
93 
94 /*TEST
95 
96    test:
97       nsize: 8
98       args: -dof 3 -stencil_width 2 -M 50 -N 50 -periodic
99 
100    test:
101       suffix: 2
102       nsize: 8
103       args: -dof 3 -stencil_width 2 -M 50 -N 50 -periodic -grid2d
104       output_file: output/ex7_1.out
105 
106    test:
107       suffix: 3
108       nsize: 8
109       args: -dof 3 -stencil_width 2 -M 50 -N 50 -periodic -grid3d
110       output_file: output/ex7_1.out
111 
112 TEST*/
113