xref: /petsc/src/mat/tests/ex159.c (revision 6a98f8dc3f2c9149905a87dc2e9d0fedaf64e09a)
1 static const char help[] = "Test MatGetLocalSubMatrix() with multiple levels of nesting.\n\n";
2 
3 #include <petscmat.h>
4 
5 int main(int argc, char *argv[])
6 {
7   PetscErrorCode ierr;
8   IS             is0a,is0b,is0,is1,isl0a,isl0b,isl0,isl1;
9   Mat            A,Aexplicit;
10   PetscBool      usenest;
11   PetscMPIInt    rank,size;
12   PetscInt       i,j;
13 
14   ierr = PetscInitialize(&argc,&argv,NULL,help);if (ierr) return ierr;
15   ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
16   ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
17 
18   {
19     PetscInt ix0a[1],ix0b[1],ix0[2],ix1[1];
20 
21     ix0a[0] = rank*2+0;
22     ix0b[0] = rank*2+1;
23     ix0[0]  = rank*3+0; ix0[1] = rank*3+1;
24     ix1[0]  = rank*3+2;
25     ierr    = ISCreateGeneral(PETSC_COMM_WORLD,1,ix0a,PETSC_COPY_VALUES,&is0a);CHKERRQ(ierr);
26     ierr    = ISCreateGeneral(PETSC_COMM_WORLD,1,ix0b,PETSC_COPY_VALUES,&is0b);CHKERRQ(ierr);
27     ierr    = ISCreateGeneral(PETSC_COMM_WORLD,2,ix0,PETSC_COPY_VALUES,&is0);CHKERRQ(ierr);
28     ierr    = ISCreateGeneral(PETSC_COMM_WORLD,1,ix1,PETSC_COPY_VALUES,&is1);CHKERRQ(ierr);
29   }
30   {
31     ierr = ISCreateStride(PETSC_COMM_SELF,6,0,1,&isl0);CHKERRQ(ierr);
32     ierr = ISCreateStride(PETSC_COMM_SELF,3,0,1,&isl0a);CHKERRQ(ierr);
33     ierr = ISCreateStride(PETSC_COMM_SELF,3,3,1,&isl0b);CHKERRQ(ierr);
34     ierr = ISCreateStride(PETSC_COMM_SELF,3,6,1,&isl1);CHKERRQ(ierr);
35   }
36 
37   usenest = PETSC_FALSE;
38   ierr    = PetscOptionsGetBool(NULL,NULL,"-nest",&usenest,NULL);CHKERRQ(ierr);
39   if (usenest) {
40     ISLocalToGlobalMapping l2g;
41     PetscInt               l2gind[3];
42     Mat                    B[9];
43 
44     l2gind[0] = (rank-1+size)%size; l2gind[1] = rank; l2gind[2] = (rank+1)%size;
45     ierr      = ISLocalToGlobalMappingCreate(PETSC_COMM_WORLD,1,3,l2gind,PETSC_COPY_VALUES,&l2g);CHKERRQ(ierr);
46     for (i=0; i<9; i++) {
47       ierr = MatCreateAIJ(PETSC_COMM_WORLD,1,1,PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE,NULL,PETSC_DECIDE,NULL,&B[i]);CHKERRQ(ierr);
48       ierr = MatSetUp(B[i]);CHKERRQ(ierr);
49       ierr = MatSetLocalToGlobalMapping(B[i],l2g,l2g);CHKERRQ(ierr);
50     }
51     {
52       IS  isx[2];
53       Mat Bx00[4],Bx01[2],Bx10[2];
54       Mat B00,B01,B10;
55 
56       isx[0]  = is0a; isx[1] = is0b;
57       Bx00[0] = B[0]; Bx00[1] = B[1]; Bx00[2] = B[3]; Bx00[3] = B[4];
58       Bx01[0] = B[2]; Bx01[1] = B[5];
59       Bx10[0] = B[6]; Bx10[1] = B[7];
60 
61       ierr = MatCreateNest(PETSC_COMM_WORLD,2,isx,2,isx,Bx00,&B00);CHKERRQ(ierr);
62       ierr = MatSetUp(B00);CHKERRQ(ierr);
63       ierr = MatCreateNest(PETSC_COMM_WORLD,2,isx,1,NULL,Bx01,&B01);CHKERRQ(ierr);
64       ierr = MatSetUp(B01);CHKERRQ(ierr);
65       ierr = MatCreateNest(PETSC_COMM_WORLD,1,NULL,2,isx,Bx10,&B10);CHKERRQ(ierr);
66       ierr = MatSetUp(B10);CHKERRQ(ierr);
67       {
68         Mat By[4];
69         IS  isy[2];
70 
71         By[0]  = B00; By[1] = B01; By[2] = B10; By[3] = B[8];
72         isy[0] = is0; isy[1] = is1;
73 
74         ierr = MatCreateNest(PETSC_COMM_WORLD,2,isy,2,isy,By,&A);CHKERRQ(ierr);
75         ierr = MatSetUp(A);CHKERRQ(ierr);
76       }
77       ierr = MatDestroy(&B00);CHKERRQ(ierr);
78       ierr = MatDestroy(&B01);CHKERRQ(ierr);
79       ierr = MatDestroy(&B10);CHKERRQ(ierr);
80     }
81     for (i=0; i<9; i++) {ierr = MatDestroy(&B[i]);CHKERRQ(ierr);}
82     ierr = ISLocalToGlobalMappingDestroy(&l2g);CHKERRQ(ierr);
83   } else {
84     ISLocalToGlobalMapping l2g;
85     PetscInt               l2gind[9];
86     for (i=0; i<3; i++) for (j=0; j<3; j++) l2gind[3*i+j] = ((rank-1+j+size) % size)*3 + i;
87     ierr = ISLocalToGlobalMappingCreate(PETSC_COMM_WORLD,1,9,l2gind,PETSC_COPY_VALUES,&l2g);CHKERRQ(ierr);
88     ierr = MatCreateAIJ(PETSC_COMM_WORLD,3,3,PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE,NULL,PETSC_DECIDE,NULL,&A);CHKERRQ(ierr);
89     ierr = MatSetLocalToGlobalMapping(A,l2g,l2g);CHKERRQ(ierr);
90     ierr = ISLocalToGlobalMappingDestroy(&l2g);CHKERRQ(ierr);
91   }
92 
93   {
94     Mat A00,A11,A0a0a,A0a0b;
95     ierr = MatGetLocalSubMatrix(A,isl0,isl0,&A00);CHKERRQ(ierr);
96     ierr = MatGetLocalSubMatrix(A,isl1,isl1,&A11);CHKERRQ(ierr);
97     ierr = MatGetLocalSubMatrix(A00,isl0a,isl0a,&A0a0a);CHKERRQ(ierr);
98     ierr = MatGetLocalSubMatrix(A00,isl0a,isl0b,&A0a0b);CHKERRQ(ierr);
99 
100     ierr = MatSetValueLocal(A0a0a,0,0,100*rank+1,ADD_VALUES);CHKERRQ(ierr);
101     ierr = MatSetValueLocal(A0a0a,0,1,100*rank+2,ADD_VALUES);CHKERRQ(ierr);
102     ierr = MatSetValueLocal(A0a0a,2,2,100*rank+9,ADD_VALUES);CHKERRQ(ierr);
103 
104     ierr = MatSetValueLocal(A0a0b,1,1,100*rank+50+5,ADD_VALUES);CHKERRQ(ierr);
105 
106     ierr = MatSetValueLocal(A11,0,0,1000*(rank+1)+1,ADD_VALUES);CHKERRQ(ierr);
107     ierr = MatSetValueLocal(A11,1,2,1000*(rank+1)+6,ADD_VALUES);CHKERRQ(ierr);
108 
109     ierr = MatRestoreLocalSubMatrix(A00,isl0a,isl0a,&A0a0a);CHKERRQ(ierr);
110     ierr = MatRestoreLocalSubMatrix(A00,isl0a,isl0b,&A0a0b);CHKERRQ(ierr);
111     ierr = MatRestoreLocalSubMatrix(A,isl0,isl0,&A00);CHKERRQ(ierr);
112     ierr = MatRestoreLocalSubMatrix(A,isl1,isl1,&A11);CHKERRQ(ierr);
113   }
114   ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
115   ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
116 
117   ierr = MatComputeOperator(A,MATAIJ,&Aexplicit);CHKERRQ(ierr);
118   ierr = MatView(Aexplicit,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
119 
120   ierr = MatDestroy(&A);CHKERRQ(ierr);
121   ierr = MatDestroy(&Aexplicit);CHKERRQ(ierr);
122   ierr = ISDestroy(&is0a);CHKERRQ(ierr);
123   ierr = ISDestroy(&is0b);CHKERRQ(ierr);
124   ierr = ISDestroy(&is0);CHKERRQ(ierr);
125   ierr = ISDestroy(&is1);CHKERRQ(ierr);
126   ierr = ISDestroy(&isl0a);CHKERRQ(ierr);
127   ierr = ISDestroy(&isl0b);CHKERRQ(ierr);
128   ierr = ISDestroy(&isl0);CHKERRQ(ierr);
129   ierr = ISDestroy(&isl1);CHKERRQ(ierr);
130   ierr = PetscFinalize();
131   return ierr;
132 }
133 
134 
135 /*TEST
136 
137    test:
138       nsize: 3
139 
140    test:
141       suffix: nest
142       nsize: 3
143       args: -nest
144 
145 TEST*/
146