1 2 static char help[] = "Reads a PETSc matrix and vector from a file and reorders it.\n\ 3 -f0 <input_file> : first file to load (small system)\n\ 4 -f1 <input_file> : second file to load (larger system)\n\n"; 5 6 /* 7 Include "petscmat.h" so that we can use matrices. 8 automatically includes: 9 petscsys.h - base PETSc routines petscvec.h - vectors 10 petscmat.h - matrices 11 petscis.h - index sets petscviewer.h - viewers 12 */ 13 #include <petscmat.h> 14 15 int main(int argc,char **args) 16 { 17 Mat A; /* matrix */ 18 PetscViewer fd; /* viewer */ 19 char file[PETSC_MAX_PATH_LEN]; /* input file name */ 20 IS isrow,iscol; /* row and column permutations */ 21 MatOrderingType rtype = MATORDERINGRCM; 22 PetscBool flg; 23 24 PetscCall(PetscInitialize(&argc,&args,(char*)0,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