Actual source code: ex5.c
2: static char help[] = "Demonstrates using ISLocalToGlobalMappings with block size.\n\n";
4: /*T
5: Concepts: local to global mappings
6: Concepts: global to local mappings
8: Description: Creates an index set based on blocks of integers. Views that index set
9: and then destroys it.
10: T*/
12: #include <petscis.h>
13: #include <petscviewer.h>
15: int main(int argc,char **argv)
16: {
17: PetscInt i,n = 4,indices[] = {0,3,9,12},m = 2,input[] = {0,2};
18: PetscInt output[2],inglobals[13],outlocals[13];
19: ISLocalToGlobalMapping mapping;
21: PetscInitialize(&argc,&argv,(char*)0,help);
23: /*
24: Create a local to global mapping. Each processor independently
25: creates a mapping
26: */
27: PetscIntView(n,indices,PETSC_VIEWER_STDOUT_WORLD);
28: ISLocalToGlobalMappingCreate(PETSC_COMM_WORLD,2,n,indices,PETSC_COPY_VALUES,&mapping);
30: /*
31: Map a set of local indices to their global values
32: */
33: PetscIntView(m,input,PETSC_VIEWER_STDOUT_WORLD);
34: ISLocalToGlobalMappingApply(mapping,m,input,output);
35: PetscIntView(m,output,PETSC_VIEWER_STDOUT_WORLD);
37: /*
38: Map some global indices to local, retaining the ones without a local index by -1
39: */
40: for (i=0; i<13; i++) inglobals[i] = i;
41: PetscIntView(13,inglobals,PETSC_VIEWER_STDOUT_WORLD);
42: ISGlobalToLocalMappingApply(mapping,IS_GTOLM_MASK,13,inglobals,NULL,outlocals);
43: PetscIntView(13,outlocals,PETSC_VIEWER_STDOUT_WORLD);
45: /*
46: Map some block global indices to local, dropping the ones without a local index.
47: */
48: PetscIntView(13,inglobals,PETSC_VIEWER_STDOUT_WORLD);
49: ISGlobalToLocalMappingApplyBlock(mapping,IS_GTOLM_DROP,13,inglobals,&m,outlocals);
50: PetscIntView(m,outlocals,PETSC_VIEWER_STDOUT_WORLD);
52: /*
53: Free the space used by the local to global mapping
54: */
55: ISLocalToGlobalMappingDestroy(&mapping);
57: PetscFinalize();
58: return 0;
59: }
61: /*TEST
63: test:
65: TEST*/