1 static char help[] = "Check the difference of the two matrices \n\ 2 Reads PETSc matrix A and B, then check B=A-B \n\ 3 Input parameters include\n\ 4 -fA <input_file> -fB <input_file> \n\n"; 5 6 #include <petscmat.h> 7 8 int main(int argc,char **args) 9 { 10 Mat A,B; 11 PetscViewer fd; 12 char file[2][PETSC_MAX_PATH_LEN]; 13 PetscBool flg; 14 PetscErrorCode ierr; 15 PetscMPIInt size; 16 PetscInt ma,na,mb,nb; 17 18 ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 19 CHKERRMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size)); 20 PetscCheckFalse(size != 1,PETSC_COMM_WORLD,PETSC_ERR_SUP,"This is a uniprocessor example only!"); 21 22 /* read the two matrices, A and B */ 23 CHKERRQ(PetscOptionsGetString(NULL,NULL,"-fA",file[0],sizeof(file[0]),&flg)); 24 PetscCheck(flg,PETSC_COMM_WORLD,PETSC_ERR_USER,"Must indicate binary file with the -fA options"); 25 CHKERRQ(PetscOptionsGetString(NULL,NULL,"-fB",file[1],sizeof(file[1]),&flg)); 26 PetscCheck(flg,PETSC_COMM_WORLD,PETSC_ERR_USER,"Must indicate binary file with the -fP options"); 27 28 /* Load matrices */ 29 CHKERRQ(PetscViewerBinaryOpen(PETSC_COMM_WORLD,file[0],FILE_MODE_READ,&fd)); 30 CHKERRQ(MatCreate(PETSC_COMM_WORLD,&A)); 31 CHKERRQ(MatLoad(A,fd)); 32 CHKERRQ(PetscViewerDestroy(&fd)); 33 printf("\n A:\n"); 34 printf("----------------------\n"); 35 CHKERRQ(MatView(A,PETSC_VIEWER_STDOUT_WORLD)); 36 CHKERRQ(MatGetSize(A,&ma,&na)); 37 38 CHKERRQ(PetscViewerBinaryOpen(PETSC_COMM_WORLD,file[1],FILE_MODE_READ,&fd)); 39 CHKERRQ(MatCreate(PETSC_COMM_WORLD,&B)); 40 CHKERRQ(MatLoad(B,fd)); 41 CHKERRQ(PetscViewerDestroy(&fd)); 42 printf("\n B:\n"); 43 printf("----------------------\n"); 44 CHKERRQ(MatView(B,PETSC_VIEWER_STDOUT_WORLD)); 45 CHKERRQ(MatGetSize(B,&mb,&nb)); 46 47 /* Compute B = -A + B */ 48 PetscCheckFalse(ma != mb || na != nb,PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"nonconforming matrix size"); 49 CHKERRQ(MatAXPY(B,-1.0,A,DIFFERENT_NONZERO_PATTERN)); 50 printf("\n B - A:\n"); 51 printf("----------------------\n"); 52 CHKERRQ(MatView(B,PETSC_VIEWER_STDOUT_WORLD)); 53 54 CHKERRQ(MatDestroy(&B)); 55 CHKERRQ(MatDestroy(&A)); 56 ierr = PetscFinalize(); 57 return ierr; 58 } 59