1 2 static char help[] = "Show MatShift BUG happening after copying a matrix with no rows on a process"; 3 /* 4 Contributed by: Eric Chamberland 5 */ 6 #include <petscmat.h> 7 8 /* DEFINE this to turn on/off the bug: */ 9 #define SET_2nd_PROC_TO_HAVE_NO_LOCAL_LINES 10 11 int main(int argc, char **args) 12 { 13 Mat C; 14 PetscInt i, m = 3; 15 PetscMPIInt rank, size; 16 PetscScalar v; 17 Mat lMatA; 18 PetscInt locallines; 19 PetscInt d_nnz[3] = {0, 0, 0}; 20 PetscInt o_nnz[3] = {0, 0, 0}; 21 22 PetscFunctionBeginUser; 23 PetscCall(PetscInitialize(&argc, &args, (char *)0, help)); 24 PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank)); 25 PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size)); 26 27 PetscCheck(2 == size, PETSC_COMM_WORLD, PETSC_ERR_ARG_INCOMP, "Relevant with 2 processes only"); 28 PetscCall(MatCreate(PETSC_COMM_WORLD, &C)); 29 30 #ifdef SET_2nd_PROC_TO_HAVE_NO_LOCAL_LINES 31 if (0 == rank) { 32 locallines = m; 33 d_nnz[0] = 1; 34 d_nnz[1] = 1; 35 d_nnz[2] = 1; 36 } else { 37 locallines = 0; 38 } 39 #else 40 if (0 == rank) { 41 locallines = m - 1; 42 d_nnz[0] = 1; 43 d_nnz[1] = 1; 44 } else { 45 locallines = 1; 46 d_nnz[0] = 1; 47 } 48 #endif 49 50 PetscCall(MatSetSizes(C, locallines, locallines, m, m)); 51 PetscCall(MatSetFromOptions(C)); 52 PetscCall(MatXAIJSetPreallocation(C, 1, d_nnz, o_nnz, NULL, NULL)); 53 54 v = 2; 55 /* Assembly on the diagonal: */ 56 for (i = 0; i < m; i++) PetscCall(MatSetValues(C, 1, &i, 1, &i, &v, ADD_VALUES)); 57 PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY)); 58 PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY)); 59 PetscCall(MatSetOption(C, MAT_NEW_NONZERO_LOCATION_ERR, PETSC_TRUE)); 60 PetscCall(MatSetOption(C, MAT_KEEP_NONZERO_PATTERN, PETSC_TRUE)); 61 PetscCall(MatView(C, PETSC_VIEWER_STDOUT_WORLD)); 62 PetscCall(MatConvert(C, MATSAME, MAT_INITIAL_MATRIX, &lMatA)); 63 PetscCall(MatView(lMatA, PETSC_VIEWER_STDOUT_WORLD)); 64 65 PetscCall(MatShift(lMatA, -1.0)); 66 67 PetscCall(MatDestroy(&lMatA)); 68 PetscCall(MatDestroy(&C)); 69 PetscCall(PetscFinalize()); 70 return 0; 71 } 72 73 /*TEST 74 75 test: 76 nsize: 2 77 78 TEST*/ 79