1 static char help[] = "Reads a PETSc matrix and vector from a file and reorders it.\n\ 2 -f0 <input_file> : first file to load (small system)\n\ 3 -f1 <input_file> : second file to load (larger system)\n\n"; 4 5 /* 6 Include "petscmat.h" so that we can use matrices. 7 automatically includes: 8 petscsys.h - base PETSc routines petscvec.h - vectors 9 petscmat.h - matrices 10 petscis.h - index sets petscviewer.h - viewers 11 */ 12 #include <petscmat.h> 13 14 int main(int argc, char **args) 15 { 16 Mat A; /* matrix */ 17 PetscViewer fd; /* viewer */ 18 char file[PETSC_MAX_PATH_LEN]; /* input file name */ 19 IS isrow, iscol; /* row and column permutations */ 20 MatOrderingType rtype = MATORDERINGRCM; 21 PetscBool flg; 22 23 PetscFunctionBeginUser; 24 PetscCall(PetscInitialize(&argc, &args, NULL, help)); 25 /* 26 Determine files from which we read the two linear systems 27 (matrix and right-hand-side vector). 28 */ 29 PetscCall(PetscOptionsGetString(NULL, NULL, "-f", file, sizeof(file), &flg)); 30 PetscCheck(flg, PETSC_COMM_WORLD, PETSC_ERR_USER, "Must indicate binary file with the -f option"); 31 32 /* ----------------------------------------------------------- 33 Beginning of loop 34 ----------------------------------------------------------- */ 35 /* 36 Loop through the reordering 2 times. 37 - The intention here is to preload and solve a small system; 38 then load another (larger) system and solve it as well. 39 This process preloads the instructions with the smaller 40 system so that more accurate performance monitoring (via 41 -log_view) can be done with the larger one (that actually 42 is the system of interest). 43 */ 44 45 /* - - - - - - - - - - - New Stage - - - - - - - - - - - - - 46 Load system i 47 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ 48 49 /* 50 Open binary file. Note that we use FILE_MODE_READ to indicate 51 reading from this file. 52 */ 53 PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD, file, FILE_MODE_READ, &fd)); 54 55 /* 56 Load the matrix; then destroy the viewer. 57 */ 58 PetscCall(MatCreate(PETSC_COMM_WORLD, &A)); 59 PetscCall(MatSetType(A, MATSEQAIJ)); 60 PetscCall(MatLoad(A, fd)); 61 PetscCall(PetscViewerDestroy(&fd)); 62 63 PetscCall(MatGetOrdering(A, rtype, &isrow, &iscol)); 64 PetscCall(ISView(isrow, PETSC_VIEWER_STDOUT_WORLD)); 65 66 /* 67 Free work space. All PETSc objects should be destroyed when they 68 are no longer needed. 69 */ 70 PetscCall(MatDestroy(&A)); 71 PetscCall(ISDestroy(&isrow)); 72 PetscCall(ISDestroy(&iscol)); 73 74 PetscCall(PetscFinalize()); 75 return 0; 76 } 77 78 /*TEST 79 80 test: 81 requires: datafilespath double !complex !defined(PETSC_USE_64BIT_INDICES) 82 args: -f ${DATAFILESPATH}/matrices/medium -viewer_binary_skip_info 83 84 TEST*/ 85