xref: /petsc/src/mat/tests/ex171.c (revision 9566063d113dddea24716c546802770db7481bc0)
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2c4762a1bSJed Brown static char help[] = "Tests MatDiagonalSet() on MatLoad() matrix \n\n";
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4c4762a1bSJed Brown #include <petscmat.h>
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6c4762a1bSJed Brown int main(int argc,char **args)
7c4762a1bSJed Brown {
8c4762a1bSJed Brown   Mat            A;
9c4762a1bSJed Brown   Vec            x;
10c4762a1bSJed Brown   PetscViewer    fd;              /* viewer */
11c4762a1bSJed Brown   char           file[PETSC_MAX_PATH_LEN]; /* input file name */
12c4762a1bSJed Brown   PetscReal      norm;
13c4762a1bSJed Brown   PetscBool      flg;
14c4762a1bSJed Brown 
15*9566063dSJacob Faibussowitsch   PetscCall(PetscInitialize(&argc,&args,(char*)0,help));
16c4762a1bSJed Brown   /* Determine file from which we read the matrix A */
17*9566063dSJacob Faibussowitsch   PetscCall(PetscOptionsGetString(NULL,NULL,"-f",file,sizeof(file),&flg));
1828b400f6SJacob Faibussowitsch   PetscCheck(flg,PETSC_COMM_WORLD,PETSC_ERR_USER,"Must indicate binary file with the -f option");
19c4762a1bSJed Brown 
20c4762a1bSJed Brown   /* Load matrix A */
21*9566063dSJacob Faibussowitsch   PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD,file,FILE_MODE_READ,&fd));
22*9566063dSJacob Faibussowitsch   PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
23*9566063dSJacob Faibussowitsch   PetscCall(MatLoad(A,fd));
24*9566063dSJacob Faibussowitsch   PetscCall(PetscViewerDestroy(&fd));
25*9566063dSJacob Faibussowitsch   PetscCall(MatCreateVecs(A,&x,NULL));
26*9566063dSJacob Faibussowitsch   PetscCall(MatGetDiagonal(A,x));
27*9566063dSJacob Faibussowitsch   PetscCall(VecScale(x,-1.0));
28*9566063dSJacob Faibussowitsch   PetscCall(MatDiagonalSet(A,x,ADD_VALUES));
29*9566063dSJacob Faibussowitsch   PetscCall(MatGetDiagonal(A,x));
30*9566063dSJacob Faibussowitsch   PetscCall(VecNorm(x,NORM_2,&norm));
31*9566063dSJacob Faibussowitsch   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Norm %g\n",(double)norm));
32c4762a1bSJed Brown 
33c4762a1bSJed Brown   /* Free data structures */
34*9566063dSJacob Faibussowitsch   PetscCall(MatDestroy(&A));
35*9566063dSJacob Faibussowitsch   PetscCall(VecDestroy(&x));
36*9566063dSJacob Faibussowitsch   PetscCall(PetscFinalize());
37b122ec5aSJacob Faibussowitsch   return 0;
38c4762a1bSJed Brown }
39c4762a1bSJed Brown 
40c4762a1bSJed Brown /*TEST
41c4762a1bSJed Brown 
42c4762a1bSJed Brown    test:
43c4762a1bSJed Brown       nsize: 4
44dfd57a17SPierre Jolivet       requires: datafilespath !complex double !defined(PETSC_USE_64BIT_INDICES)
45c4762a1bSJed Brown       args: -f ${wPETSC_DIR}/share/petsc/datafiles/matrices/ns-real-int32-float64 -malloc_dump
46c4762a1bSJed Brown 
47c4762a1bSJed Brown TEST*/
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