xref: /petsc/src/mat/tests/ex124.c (revision 327415f76d85372a4417cf1aaa14db707d4d6c04)
1c4762a1bSJed Brown static char help[] = "Check the difference of the two matrices \n\
2c4762a1bSJed Brown Reads PETSc matrix A and B, then check B=A-B \n\
3c4762a1bSJed Brown Input parameters include\n\
4c4762a1bSJed Brown   -fA <input_file> -fB <input_file> \n\n";
5c4762a1bSJed Brown 
6c4762a1bSJed Brown #include <petscmat.h>
7c4762a1bSJed Brown 
8ad0e0ea3SStefano Zampini int main(int argc,char **args)
9c4762a1bSJed Brown {
10c4762a1bSJed Brown   Mat            A,B;
11c4762a1bSJed Brown   PetscViewer    fd;
12c4762a1bSJed Brown   char           file[2][PETSC_MAX_PATH_LEN];
13c4762a1bSJed Brown   PetscBool      flg;
14c4762a1bSJed Brown   PetscMPIInt    size;
15c4762a1bSJed Brown   PetscInt       ma,na,mb,nb;
16c4762a1bSJed Brown 
17*327415f7SBarry Smith   PetscFunctionBeginUser;
189566063dSJacob Faibussowitsch   PetscCall(PetscInitialize(&argc,&args,(char*)0,help));
199566063dSJacob Faibussowitsch   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD,&size));
20be096a46SBarry Smith   PetscCheck(size == 1,PETSC_COMM_WORLD,PETSC_ERR_WRONG_MPI_SIZE,"This is a uniprocessor example only!");
21c4762a1bSJed Brown 
22c4762a1bSJed Brown   /* read the two matrices, A and B */
239566063dSJacob Faibussowitsch   PetscCall(PetscOptionsGetString(NULL,NULL,"-fA",file[0],sizeof(file[0]),&flg));
2428b400f6SJacob Faibussowitsch   PetscCheck(flg,PETSC_COMM_WORLD,PETSC_ERR_USER,"Must indicate binary file with the -fA options");
259566063dSJacob Faibussowitsch   PetscCall(PetscOptionsGetString(NULL,NULL,"-fB",file[1],sizeof(file[1]),&flg));
2628b400f6SJacob Faibussowitsch   PetscCheck(flg,PETSC_COMM_WORLD,PETSC_ERR_USER,"Must indicate binary file with the -fP options");
27c4762a1bSJed Brown 
28c4762a1bSJed Brown   /* Load matrices */
299566063dSJacob Faibussowitsch   PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD,file[0],FILE_MODE_READ,&fd));
309566063dSJacob Faibussowitsch   PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
319566063dSJacob Faibussowitsch   PetscCall(MatLoad(A,fd));
329566063dSJacob Faibussowitsch   PetscCall(PetscViewerDestroy(&fd));
33c4762a1bSJed Brown   printf("\n A:\n");
34c4762a1bSJed Brown   printf("----------------------\n");
359566063dSJacob Faibussowitsch   PetscCall(MatView(A,PETSC_VIEWER_STDOUT_WORLD));
369566063dSJacob Faibussowitsch   PetscCall(MatGetSize(A,&ma,&na));
37c4762a1bSJed Brown 
389566063dSJacob Faibussowitsch   PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD,file[1],FILE_MODE_READ,&fd));
399566063dSJacob Faibussowitsch   PetscCall(MatCreate(PETSC_COMM_WORLD,&B));
409566063dSJacob Faibussowitsch   PetscCall(MatLoad(B,fd));
419566063dSJacob Faibussowitsch   PetscCall(PetscViewerDestroy(&fd));
42c4762a1bSJed Brown   printf("\n B:\n");
43c4762a1bSJed Brown   printf("----------------------\n");
449566063dSJacob Faibussowitsch   PetscCall(MatView(B,PETSC_VIEWER_STDOUT_WORLD));
459566063dSJacob Faibussowitsch   PetscCall(MatGetSize(B,&mb,&nb));
46c4762a1bSJed Brown 
47c4762a1bSJed Brown   /* Compute B = -A + B */
48e00437b9SBarry Smith   PetscCheck(ma == mb && na == nb,PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"nonconforming matrix size");
499566063dSJacob Faibussowitsch   PetscCall(MatAXPY(B,-1.0,A,DIFFERENT_NONZERO_PATTERN));
50c4762a1bSJed Brown   printf("\n B - A:\n");
51c4762a1bSJed Brown   printf("----------------------\n");
529566063dSJacob Faibussowitsch   PetscCall(MatView(B,PETSC_VIEWER_STDOUT_WORLD));
53c4762a1bSJed Brown 
549566063dSJacob Faibussowitsch   PetscCall(MatDestroy(&B));
559566063dSJacob Faibussowitsch   PetscCall(MatDestroy(&A));
569566063dSJacob Faibussowitsch   PetscCall(PetscFinalize());
57b122ec5aSJacob Faibussowitsch   return 0;
58c4762a1bSJed Brown }
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