xref: /petsc/src/mat/tests/ex139.c (revision d5b43468fb8780a8feea140ccd6fa3e6a50411cc)
1 
2 const char help[] = "Test MatCreateLocalRef()\n\n";
3 
4 #include <petscmat.h>
5 
6 static PetscErrorCode GetLocalRef(Mat A, IS isrow, IS iscol, Mat *B)
7 {
8   IS istmp;
9 
10   PetscFunctionBegin;
11   PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Extracting LocalRef with isrow:\n"));
12   PetscCall(ISOnComm(isrow, PETSC_COMM_WORLD, PETSC_COPY_VALUES, &istmp));
13   PetscCall(ISView(istmp, PETSC_VIEWER_STDOUT_WORLD));
14   PetscCall(ISDestroy(&istmp));
15   PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Extracting LocalRef with iscol (only rank=0 shown):\n"));
16   PetscCall(ISOnComm(iscol, PETSC_COMM_WORLD, PETSC_COPY_VALUES, &istmp));
17   PetscCall(ISView(istmp, PETSC_VIEWER_STDOUT_WORLD));
18   PetscCall(ISDestroy(&istmp));
19 
20   PetscCall(MatCreateLocalRef(A, isrow, iscol, B));
21   PetscFunctionReturn(0);
22 }
23 
24 int main(int argc, char *argv[])
25 {
26   MPI_Comm               comm;
27   Mat                    J, B;
28   PetscInt               i, j, k, l, rstart, rend, m, n, top_bs, row_bs, col_bs, nlocblocks, *idx, nrowblocks, ncolblocks, *ridx, *cidx, *icol, *irow;
29   PetscScalar           *vals;
30   ISLocalToGlobalMapping brmap;
31   IS                     is0, is1;
32   PetscBool              diag, blocked;
33 
34   PetscFunctionBeginUser;
35   PetscCall(PetscInitialize(&argc, &argv, 0, help));
36   comm = PETSC_COMM_WORLD;
37 
38   PetscOptionsBegin(comm, NULL, "LocalRef Test Options", NULL);
39   {
40     top_bs  = 2;
41     row_bs  = 2;
42     col_bs  = 2;
43     diag    = PETSC_FALSE;
44     blocked = PETSC_FALSE;
45     PetscCall(PetscOptionsInt("-top_bs", "Block size of top-level matrix", 0, top_bs, &top_bs, NULL));
46     PetscCall(PetscOptionsInt("-row_bs", "Block size of row map", 0, row_bs, &row_bs, NULL));
47     PetscCall(PetscOptionsInt("-col_bs", "Block size of col map", 0, col_bs, &col_bs, NULL));
48     PetscCall(PetscOptionsBool("-diag", "Extract a diagonal black", 0, diag, &diag, NULL));
49     PetscCall(PetscOptionsBool("-blocked", "Use block insertion", 0, blocked, &blocked, NULL));
50   }
51   PetscOptionsEnd();
52 
53   PetscCall(MatCreate(comm, &J));
54   PetscCall(MatSetSizes(J, 6, 6, PETSC_DETERMINE, PETSC_DETERMINE));
55   PetscCall(MatSetBlockSize(J, top_bs));
56   PetscCall(MatSetFromOptions(J));
57   PetscCall(MatSeqBAIJSetPreallocation(J, top_bs, PETSC_DECIDE, 0));
58   PetscCall(MatMPIBAIJSetPreallocation(J, top_bs, PETSC_DECIDE, 0, PETSC_DECIDE, 0));
59   PetscCall(MatSetUp(J));
60   PetscCall(MatGetSize(J, &m, &n));
61   PetscCall(MatGetOwnershipRange(J, &rstart, &rend));
62 
63   nlocblocks = (rend - rstart) / top_bs + 2;
64   PetscCall(PetscMalloc1(nlocblocks, &idx));
65   for (i = 0; i < nlocblocks; i++) idx[i] = (rstart / top_bs + i - 1 + m / top_bs) % (m / top_bs);
66   PetscCall(ISLocalToGlobalMappingCreate(comm, top_bs, nlocblocks, idx, PETSC_OWN_POINTER, &brmap));
67   PetscCall(PetscPrintf(comm, "Block ISLocalToGlobalMapping:\n"));
68   PetscCall(ISLocalToGlobalMappingView(brmap, PETSC_VIEWER_STDOUT_WORLD));
69 
70   PetscCall(MatSetLocalToGlobalMapping(J, brmap, brmap));
71   PetscCall(ISLocalToGlobalMappingDestroy(&brmap));
72 
73   /* Create index sets for local submatrix */
74   nrowblocks = (rend - rstart) / row_bs;
75   ncolblocks = (rend - rstart) / col_bs;
76   PetscCall(PetscMalloc2(nrowblocks, &ridx, ncolblocks, &cidx));
77   for (i = 0; i < nrowblocks; i++) ridx[i] = i + ((i > nrowblocks / 2) ^ !rstart);
78   for (i = 0; i < ncolblocks; i++) cidx[i] = i + ((i < ncolblocks / 2) ^ !!rstart);
79   PetscCall(ISCreateBlock(PETSC_COMM_SELF, row_bs, nrowblocks, ridx, PETSC_COPY_VALUES, &is0));
80   PetscCall(ISCreateBlock(PETSC_COMM_SELF, col_bs, ncolblocks, cidx, PETSC_COPY_VALUES, &is1));
81   PetscCall(PetscFree2(ridx, cidx));
82 
83   if (diag) {
84     PetscCall(ISDestroy(&is1));
85     PetscCall(PetscObjectReference((PetscObject)is0));
86     is1        = is0;
87     ncolblocks = nrowblocks;
88   }
89 
90   PetscCall(GetLocalRef(J, is0, is1, &B));
91 
92   PetscCall(MatZeroEntries(J));
93 
94   PetscCall(PetscMalloc3(row_bs, &irow, col_bs, &icol, row_bs * col_bs, &vals));
95   for (i = 0; i < nrowblocks; i++) {
96     for (j = 0; j < ncolblocks; j++) {
97       for (k = 0; k < row_bs; k++) {
98         for (l = 0; l < col_bs; l++) vals[k * col_bs + l] = i * 100000 + j * 1000 + k * 10 + l;
99         irow[k] = i * row_bs + k;
100       }
101       for (l = 0; l < col_bs; l++) icol[l] = j * col_bs + l;
102       if (blocked) {
103         PetscCall(MatSetValuesBlockedLocal(B, 1, &i, 1, &j, vals, ADD_VALUES));
104       } else {
105         PetscCall(MatSetValuesLocal(B, row_bs, irow, col_bs, icol, vals, ADD_VALUES));
106       }
107     }
108   }
109   PetscCall(PetscFree3(irow, icol, vals));
110 
111   PetscCall(MatAssemblyBegin(J, MAT_FINAL_ASSEMBLY));
112   PetscCall(MatAssemblyEnd(J, MAT_FINAL_ASSEMBLY));
113 
114   PetscCall(MatView(J, PETSC_VIEWER_STDOUT_WORLD));
115 
116   PetscCall(ISDestroy(&is0));
117   PetscCall(ISDestroy(&is1));
118   PetscCall(MatDestroy(&B));
119   PetscCall(MatDestroy(&J));
120   PetscCall(PetscFinalize());
121   return 0;
122 }
123 
124 /*TEST
125 
126    test:
127       nsize: 2
128       filter: grep -v "type: mpi"
129       args: -blocked {{0 1}} -mat_type {{aij baij}}
130 
131 TEST*/
132