Actual source code: ex124.c
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";
6: #include petscmat.h
8: #undef WRITEFILE
11: PetscInt main(PetscInt argc,char **args)
12: {
13: Mat A,B;
14: PetscViewer fd;
15: char file[2][PETSC_MAX_PATH_LEN];
16: PetscTruth flg;
18: PetscMPIInt size;
19: PetscInt ma,na,mb,nb;
21: PetscInitialize(&argc,&args,(char *)0,help);
22: MPI_Comm_size(PETSC_COMM_WORLD,&size);
23: if (size != 1) SETERRQ(PETSC_ERR_SUP,"This is a uniprocessor example only!");
25: /* read the two matrices, A and B */
26: PetscOptionsGetString(PETSC_NULL,"-fA",file[0],PETSC_MAX_PATH_LEN-1,&flg);
27: if (!flg) SETERRQ(PETSC_ERR_USER,"Must indicate binary file with the -fA options");
28: PetscOptionsGetString(PETSC_NULL,"-fB",file[1],PETSC_MAX_PATH_LEN-1,&flg);
29: if (!flg) SETERRQ(PETSC_ERR_USER,"Must indicate binary file with the -fP options");
30:
31: /* Load matrices */
32: PetscViewerBinaryOpen(PETSC_COMM_WORLD,file[0],FILE_MODE_READ,&fd);
33: MatLoad(fd,MATAIJ,&A);
34: PetscViewerDestroy(fd);
35: printf("\n A:\n");
36: printf("----------------------\n");
37: MatView(A,PETSC_VIEWER_STDOUT_WORLD);
38: MatGetSize(A,&ma,&na);
39:
40:
41: PetscViewerBinaryOpen(PETSC_COMM_WORLD,file[1],FILE_MODE_READ,&fd);
42: MatLoad(fd,MATAIJ,&B);
43: PetscViewerDestroy(fd);
44: printf("\n B:\n");
45: printf("----------------------\n");
46: MatView(B,PETSC_VIEWER_STDOUT_WORLD);
47: MatGetSize(B,&mb,&nb);
48:
49: /* Compute B = -A + B */
50: if (ma != mb || na != nb) SETERRQ(PETSC_ERR_ARG_SIZ,"nonconforming matrix size");
51: MatAXPY(B,-1.0,A,DIFFERENT_NONZERO_PATTERN);
52: printf("\n B - A:\n");
53: printf("----------------------\n");
54: MatView(B,PETSC_VIEWER_STDOUT_WORLD);
56: MatDestroy(B);
57: MatDestroy(A);
58: PetscFinalize();
59: return 0;
60: }