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