xref: /petsc/src/dm/tests/ex51.c (revision b122ec5aa1bd4469eb4e0673542fb7de3f411254)
1c4762a1bSJed Brown 
2c4762a1bSJed Brown static char help[] = "Tests DMDAGlobalToNaturalAllCreate() using contour plotting for 2d DMDAs.\n\n";
3c4762a1bSJed Brown 
4c4762a1bSJed Brown #include <petscdm.h>
5c4762a1bSJed Brown #include <petscdmda.h>
6c4762a1bSJed Brown #include <petscdraw.h>
7c4762a1bSJed Brown 
8c4762a1bSJed Brown int main(int argc,char **argv)
9c4762a1bSJed Brown {
10c4762a1bSJed Brown   PetscInt         i,j,M = 10,N = 8,m = PETSC_DECIDE,n = PETSC_DECIDE;
11c4762a1bSJed Brown   PetscMPIInt      rank;
12c4762a1bSJed Brown   PetscBool        flg = PETSC_FALSE;
13c4762a1bSJed Brown   DM               da;
14c4762a1bSJed Brown   PetscViewer      viewer;
15c4762a1bSJed Brown   Vec              localall,global;
16c4762a1bSJed Brown   PetscScalar      value,*vlocal;
17c4762a1bSJed Brown   DMBoundaryType   bx    = DM_BOUNDARY_NONE,by = DM_BOUNDARY_NONE;
18c4762a1bSJed Brown   DMDAStencilType  stype = DMDA_STENCIL_BOX;
19c4762a1bSJed Brown   VecScatter       tolocalall,fromlocalall;
20c4762a1bSJed Brown   PetscInt         start,end;
21c4762a1bSJed Brown 
22*b122ec5aSJacob Faibussowitsch   CHKERRQ(PetscInitialize(&argc,&argv,(char*)0,help));
235f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscViewerDrawOpen(PETSC_COMM_WORLD,0,"",300,0,300,300,&viewer));
24c4762a1bSJed Brown 
25c4762a1bSJed Brown   /* Read options */
265f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-M",&M,NULL));
275f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-N",&N,NULL));
285f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL));
295f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
305f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscOptionsGetBool(NULL,NULL,"-star_stencil",&flg,NULL));
31c4762a1bSJed Brown   if (flg) stype = DMDA_STENCIL_STAR;
32c4762a1bSJed Brown 
33c4762a1bSJed Brown   /* Create distributed array and get vectors */
345f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDACreate2d(PETSC_COMM_WORLD,bx,by,stype,M,N,m,n,1,1,NULL,NULL,&da));
355f80ce2aSJacob Faibussowitsch   CHKERRQ(DMSetFromOptions(da));
365f80ce2aSJacob Faibussowitsch   CHKERRQ(DMSetUp(da));
37c4762a1bSJed Brown 
385f80ce2aSJacob Faibussowitsch   CHKERRQ(DMCreateGlobalVector(da,&global));
395f80ce2aSJacob Faibussowitsch   CHKERRQ(VecCreateSeq(PETSC_COMM_SELF,M*N,&localall));
40c4762a1bSJed Brown 
415f80ce2aSJacob Faibussowitsch   CHKERRMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank));
425f80ce2aSJacob Faibussowitsch   CHKERRQ(VecGetOwnershipRange(global,&start,&end));
43c4762a1bSJed Brown   for (i=start; i<end; i++) {
44c4762a1bSJed Brown     value = 5.0*rank;
455f80ce2aSJacob Faibussowitsch     CHKERRQ(VecSetValues(global,1,&i,&value,INSERT_VALUES));
46c4762a1bSJed Brown   }
475f80ce2aSJacob Faibussowitsch   CHKERRQ(VecView(global,viewer));
48c4762a1bSJed Brown 
49c4762a1bSJed Brown   /*
50c4762a1bSJed Brown      Create Scatter from global DMDA parallel vector to local vector that
51c4762a1bSJed Brown    contains all entries
52c4762a1bSJed Brown   */
535f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDAGlobalToNaturalAllCreate(da,&tolocalall));
545f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDANaturalAllToGlobalCreate(da,&fromlocalall));
55c4762a1bSJed Brown 
565f80ce2aSJacob Faibussowitsch   CHKERRQ(VecScatterBegin(tolocalall,global,localall,INSERT_VALUES,SCATTER_FORWARD));
575f80ce2aSJacob Faibussowitsch   CHKERRQ(VecScatterEnd(tolocalall,global,localall,INSERT_VALUES,SCATTER_FORWARD));
58c4762a1bSJed Brown 
595f80ce2aSJacob Faibussowitsch   CHKERRQ(VecGetArray(localall,&vlocal));
60c4762a1bSJed Brown   for (j=0; j<N; j++) {
61c4762a1bSJed Brown     for (i=0; i<M; i++) {
62c4762a1bSJed Brown       *vlocal++ += i + j*M;
63c4762a1bSJed Brown     }
64c4762a1bSJed Brown   }
655f80ce2aSJacob Faibussowitsch   CHKERRQ(VecRestoreArray(localall,&vlocal));
66c4762a1bSJed Brown 
67c4762a1bSJed Brown   /* scatter back to global vector */
685f80ce2aSJacob Faibussowitsch   CHKERRQ(VecScatterBegin(fromlocalall,localall,global,INSERT_VALUES,SCATTER_FORWARD));
695f80ce2aSJacob Faibussowitsch   CHKERRQ(VecScatterEnd(fromlocalall,localall,global,INSERT_VALUES,SCATTER_FORWARD));
70c4762a1bSJed Brown 
715f80ce2aSJacob Faibussowitsch   CHKERRQ(VecView(global,viewer));
72c4762a1bSJed Brown 
73c4762a1bSJed Brown   /* Free memory */
745f80ce2aSJacob Faibussowitsch   CHKERRQ(VecScatterDestroy(&tolocalall));
755f80ce2aSJacob Faibussowitsch   CHKERRQ(VecScatterDestroy(&fromlocalall));
765f80ce2aSJacob Faibussowitsch   CHKERRQ(PetscViewerDestroy(&viewer));
775f80ce2aSJacob Faibussowitsch   CHKERRQ(VecDestroy(&localall));
785f80ce2aSJacob Faibussowitsch   CHKERRQ(VecDestroy(&global));
795f80ce2aSJacob Faibussowitsch   CHKERRQ(DMDestroy(&da));
80*b122ec5aSJacob Faibussowitsch   CHKERRQ(PetscFinalize());
81*b122ec5aSJacob Faibussowitsch   return 0;
82c4762a1bSJed Brown }
83c4762a1bSJed Brown 
84c4762a1bSJed Brown /*TEST
85c4762a1bSJed Brown 
86c4762a1bSJed Brown    build:
87c4762a1bSJed Brown      requires: !complex
88c4762a1bSJed Brown 
89c4762a1bSJed Brown    test:
90c4762a1bSJed Brown       nsize: 3
91c4762a1bSJed Brown 
92c4762a1bSJed Brown TEST*/
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