xref: /petsc/src/mat/tests/ex300.c (revision 9566063d113dddea24716c546802770db7481bc0)
1c4762a1bSJed Brown 
2c4762a1bSJed Brown static char help[] = "Show MatShift BUG happening after copying a matrix with no rows on a process";
3c4762a1bSJed Brown /*
4c4762a1bSJed Brown    Contributed by: Eric Chamberland
5c4762a1bSJed Brown */
6c4762a1bSJed Brown #include <petscmat.h>
7c4762a1bSJed Brown 
8c4762a1bSJed Brown /* DEFINE this to turn on/off the bug: */
9c4762a1bSJed Brown #define SET_2nd_PROC_TO_HAVE_NO_LOCAL_LINES
10c4762a1bSJed Brown 
11c4762a1bSJed Brown int main(int argc,char **args)
12c4762a1bSJed Brown {
13c4762a1bSJed Brown   Mat               C;
14c4762a1bSJed Brown   PetscInt          i,m = 3;
15c4762a1bSJed Brown   PetscMPIInt       rank,size;
16c4762a1bSJed Brown   PetscScalar       v;
17c4762a1bSJed Brown   Mat               lMatA;
18c4762a1bSJed Brown   PetscInt          locallines;
19c4762a1bSJed Brown   PetscInt          d_nnz[3] = {0,0,0};
20c4762a1bSJed Brown   PetscInt          o_nnz[3] = {0,0,0};
21c4762a1bSJed Brown 
22*9566063dSJacob Faibussowitsch   PetscCall(PetscInitialize(&argc,&args,(char*)0,help));
23*9566063dSJacob Faibussowitsch   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD,&rank));
24*9566063dSJacob Faibussowitsch   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size));
25c4762a1bSJed Brown 
262c71b3e2SJacob Faibussowitsch   PetscCheckFalse(2 != size,PETSC_COMM_WORLD,PETSC_ERR_ARG_INCOMP,"Relevant with 2 processes only");
27*9566063dSJacob Faibussowitsch   PetscCall(MatCreate(PETSC_COMM_WORLD,&C));
28c4762a1bSJed Brown 
29c4762a1bSJed Brown #ifdef SET_2nd_PROC_TO_HAVE_NO_LOCAL_LINES
30c4762a1bSJed Brown   if (0 == rank) {
31c4762a1bSJed Brown     locallines = m;
32c4762a1bSJed Brown     d_nnz[0] = 1;
33c4762a1bSJed Brown     d_nnz[1] = 1;
34c4762a1bSJed Brown     d_nnz[2] = 1;
35c4762a1bSJed Brown   } else {
36c4762a1bSJed Brown    locallines = 0;
37c4762a1bSJed Brown   }
38c4762a1bSJed Brown #else
39c4762a1bSJed Brown   if (0 == rank) {
40c4762a1bSJed Brown     locallines = m-1;
41c4762a1bSJed Brown     d_nnz[0] = 1;
42c4762a1bSJed Brown     d_nnz[1] = 1;
43c4762a1bSJed Brown   } else {
44c4762a1bSJed Brown     locallines = 1;
45c4762a1bSJed Brown     d_nnz[0] = 1;
46c4762a1bSJed Brown   }
47c4762a1bSJed Brown #endif
48c4762a1bSJed Brown 
49*9566063dSJacob Faibussowitsch   PetscCall(MatSetSizes(C,locallines,locallines,m,m));
50*9566063dSJacob Faibussowitsch   PetscCall(MatSetFromOptions(C));
51*9566063dSJacob Faibussowitsch   PetscCall(MatXAIJSetPreallocation(C,1,d_nnz,o_nnz,NULL,NULL));
52c4762a1bSJed Brown 
53c4762a1bSJed Brown   v = 2;
54c4762a1bSJed Brown   /* Assembly on the diagonal: */
55c4762a1bSJed Brown   for (i=0; i<m; i++) {
56*9566063dSJacob Faibussowitsch      PetscCall(MatSetValues(C,1,&i,1,&i,&v,ADD_VALUES));
57c4762a1bSJed Brown   }
58*9566063dSJacob Faibussowitsch   PetscCall(MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY));
59*9566063dSJacob Faibussowitsch   PetscCall(MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY));
60*9566063dSJacob Faibussowitsch   PetscCall(MatSetOption(C,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE));
61*9566063dSJacob Faibussowitsch   PetscCall(MatSetOption(C, MAT_KEEP_NONZERO_PATTERN, PETSC_TRUE));
62*9566063dSJacob Faibussowitsch   PetscCall(MatView(C,PETSC_VIEWER_STDOUT_WORLD));
63*9566063dSJacob Faibussowitsch   PetscCall(MatConvert(C,MATSAME, MAT_INITIAL_MATRIX, &lMatA));
64*9566063dSJacob Faibussowitsch   PetscCall(MatView(lMatA,PETSC_VIEWER_STDOUT_WORLD));
65c4762a1bSJed Brown 
66*9566063dSJacob Faibussowitsch   PetscCall(MatShift(lMatA,-1.0));
67c4762a1bSJed Brown 
68*9566063dSJacob Faibussowitsch   PetscCall(MatDestroy(&lMatA));
69*9566063dSJacob Faibussowitsch   PetscCall(MatDestroy(&C));
70*9566063dSJacob Faibussowitsch   PetscCall(PetscFinalize());
71b122ec5aSJacob Faibussowitsch   return 0;
72c4762a1bSJed Brown }
73c4762a1bSJed Brown 
74c4762a1bSJed Brown /*TEST
75c4762a1bSJed Brown 
76c4762a1bSJed Brown    test:
77c4762a1bSJed Brown       nsize: 2
78c4762a1bSJed Brown 
79c4762a1bSJed Brown TEST*/
80