1 2 static char help[] = "Tests MatDiagonalSet() on MatLoad() matrix \n\n"; 3 4 #include <petscmat.h> 5 6 int main(int argc,char **args) 7 { 8 Mat A; 9 Vec x; 10 PetscErrorCode ierr; 11 PetscViewer fd; /* viewer */ 12 char file[PETSC_MAX_PATH_LEN]; /* input file name */ 13 PetscReal norm; 14 PetscBool flg; 15 16 ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 17 /* Determine file from which we read the matrix A */ 18 ierr = PetscOptionsGetString(NULL,NULL,"-f",file,sizeof(file),&flg);CHKERRQ(ierr); 19 PetscCheckFalse(!flg,PETSC_COMM_WORLD,PETSC_ERR_USER,"Must indicate binary file with the -f option"); 20 21 /* Load matrix A */ 22 ierr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd);CHKERRQ(ierr); 23 ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr); 24 ierr = MatLoad(A,fd);CHKERRQ(ierr); 25 ierr = PetscViewerDestroy(&fd);CHKERRQ(ierr); 26 ierr = MatCreateVecs(A,&x,NULL);CHKERRQ(ierr); 27 ierr = MatGetDiagonal(A,x);CHKERRQ(ierr); 28 ierr = VecScale(x,-1.0);CHKERRQ(ierr); 29 ierr = MatDiagonalSet(A,x,ADD_VALUES);CHKERRQ(ierr); 30 ierr = MatGetDiagonal(A,x);CHKERRQ(ierr); 31 ierr = VecNorm(x,NORM_2,&norm);CHKERRQ(ierr); 32 ierr = PetscPrintf(PETSC_COMM_WORLD,"Norm %g\n",(double)norm);CHKERRQ(ierr); 33 34 /* Free data structures */ 35 ierr = MatDestroy(&A);CHKERRQ(ierr); 36 ierr = VecDestroy(&x);CHKERRQ(ierr); 37 ierr = PetscFinalize(); 38 return ierr; 39 } 40 41 /*TEST 42 43 test: 44 nsize: 4 45 requires: datafilespath !complex double !defined(PETSC_USE_64BIT_INDICES) 46 args: -f ${wPETSC_DIR}/share/petsc/datafiles/matrices/ns-real-int32-float64 -malloc_dump 47 48 TEST*/ 49