1 2 static char help[] = "Tests converting a matrix to another format with MatConvert().\n\n"; 3 4 #include <petscmat.h> 5 6 int main(int argc, char **args) { 7 Mat C, A; 8 PetscInt i, j, m = 5, n = 4, Ii, J; 9 PetscMPIInt rank, size; 10 PetscScalar v; 11 char mtype[256]; 12 13 PetscFunctionBeginUser; 14 PetscCall(PetscInitialize(&argc, &args, (char *)0, help)); 15 PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank)); 16 17 /* This example does not work correctly for np > 2 */ 18 PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size)); 19 PetscCheck(size <= 2, PETSC_COMM_WORLD, PETSC_ERR_WRONG_MPI_SIZE, "Use np <= 2"); 20 21 /* Create the matrix for the five point stencil, YET AGAIN */ 22 PetscCall(MatCreate(PETSC_COMM_WORLD, &C)); 23 PetscCall(MatSetSizes(C, PETSC_DECIDE, PETSC_DECIDE, m * n, m * n)); 24 PetscCall(MatSetFromOptions(C)); 25 PetscCall(MatSetUp(C)); 26 for (i = 0; i < m; i++) { 27 for (j = 2 * rank; j < 2 * rank + 2; j++) { 28 v = -1.0; 29 Ii = j + n * i; 30 if (i > 0) { 31 J = Ii - n; 32 PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES)); 33 } 34 if (i < m - 1) { 35 J = Ii + n; 36 PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES)); 37 } 38 if (j > 0) { 39 J = Ii - 1; 40 PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES)); 41 } 42 if (j < n - 1) { 43 J = Ii + 1; 44 PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES)); 45 } 46 v = 4.0; 47 PetscCall(MatSetValues(C, 1, &Ii, 1, &Ii, &v, INSERT_VALUES)); 48 } 49 } 50 51 PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY)); 52 PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY)); 53 PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_INFO)); 54 PetscCall(MatView(C, PETSC_VIEWER_STDOUT_WORLD)); 55 PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD)); 56 PetscCall(MatView(C, PETSC_VIEWER_STDOUT_WORLD)); 57 58 PetscCall(PetscStrcpy(mtype, MATSAME)); 59 PetscCall(PetscOptionsGetString(NULL, NULL, "-conv_mat_type", mtype, sizeof(mtype), NULL)); 60 PetscCall(MatConvert(C, mtype, MAT_INITIAL_MATRIX, &A)); 61 PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_INFO)); 62 PetscCall(MatView(A, PETSC_VIEWER_STDOUT_WORLD)); 63 PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD)); 64 PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_IMPL)); 65 PetscCall(MatView(A, PETSC_VIEWER_STDOUT_WORLD)); 66 PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD)); 67 68 /* Free data structures */ 69 PetscCall(MatDestroy(&A)); 70 PetscCall(MatDestroy(&C)); 71 72 PetscCall(PetscFinalize()); 73 return 0; 74 } 75 76 /*TEST 77 78 test: 79 args: -conv_mat_type seqaij 80 81 TEST*/ 82