xref: /petsc/src/mat/tests/ex11.c (revision 327415f76d85372a4417cf1aaa14db707d4d6c04)
1c4762a1bSJed Brown 
2c4762a1bSJed Brown static char help[] = "Tests the use of MatZeroRows() for uniprocessor matrices.\n\n";
3c4762a1bSJed Brown 
4c4762a1bSJed Brown #include <petscmat.h>
5c4762a1bSJed Brown 
6c4762a1bSJed Brown int main(int argc,char **args)
7c4762a1bSJed Brown {
8c4762a1bSJed Brown   Mat            C;
9c4762a1bSJed Brown   PetscInt       i,j,m = 5,n = 5,Ii,J;
10c4762a1bSJed Brown   PetscScalar    v,five = 5.0;
11c4762a1bSJed Brown   IS             isrow;
12c4762a1bSJed Brown   PetscBool      keepnonzeropattern;
13c4762a1bSJed Brown 
14*327415f7SBarry Smith   PetscFunctionBeginUser;
159566063dSJacob Faibussowitsch   PetscCall(PetscInitialize(&argc,&args,(char*)0,help));
16c4762a1bSJed Brown   /* create the matrix for the five point stencil, YET AGAIN*/
179566063dSJacob Faibussowitsch   PetscCall(MatCreate(PETSC_COMM_SELF,&C));
189566063dSJacob Faibussowitsch   PetscCall(MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n));
199566063dSJacob Faibussowitsch   PetscCall(MatSetFromOptions(C));
209566063dSJacob Faibussowitsch   PetscCall(MatSetUp(C));
21c4762a1bSJed Brown   for (i=0; i<m; i++) {
22c4762a1bSJed Brown     for (j=0; j<n; j++) {
23c4762a1bSJed Brown       v = -1.0;  Ii = j + n*i;
249566063dSJacob Faibussowitsch       if (i>0)   {J = Ii - n; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
259566063dSJacob Faibussowitsch       if (i<m-1) {J = Ii + n; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
269566063dSJacob Faibussowitsch       if (j>0)   {J = Ii - 1; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
279566063dSJacob Faibussowitsch       if (j<n-1) {J = Ii + 1; PetscCall(MatSetValues(C,1,&Ii,1,&J,&v,INSERT_VALUES));}
289566063dSJacob Faibussowitsch       v = 4.0; PetscCall(MatSetValues(C,1,&Ii,1,&Ii,&v,INSERT_VALUES));
29c4762a1bSJed Brown     }
30c4762a1bSJed Brown   }
319566063dSJacob Faibussowitsch   PetscCall(MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY));
329566063dSJacob Faibussowitsch   PetscCall(MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY));
33c4762a1bSJed Brown 
349566063dSJacob Faibussowitsch   PetscCall(ISCreateStride(PETSC_COMM_SELF,(m*n)/2,0,2,&isrow));
35c4762a1bSJed Brown 
369566063dSJacob Faibussowitsch   PetscCall(PetscOptionsHasName(NULL,NULL,"-keep_nonzero_pattern",&keepnonzeropattern));
371baa6e33SBarry Smith   if (keepnonzeropattern) PetscCall(MatSetOption(C,MAT_KEEP_NONZERO_PATTERN,PETSC_TRUE));
38c4762a1bSJed Brown 
399566063dSJacob Faibussowitsch   PetscCall(MatZeroRowsIS(C,isrow,five,0,0));
40c4762a1bSJed Brown 
419566063dSJacob Faibussowitsch   PetscCall(MatView(C,PETSC_VIEWER_STDOUT_SELF));
42c4762a1bSJed Brown 
439566063dSJacob Faibussowitsch   PetscCall(ISDestroy(&isrow));
449566063dSJacob Faibussowitsch   PetscCall(MatDestroy(&C));
459566063dSJacob Faibussowitsch   PetscCall(PetscFinalize());
46b122ec5aSJacob Faibussowitsch   return 0;
47c4762a1bSJed Brown }
48c4762a1bSJed Brown 
49c4762a1bSJed Brown /*TEST
50c4762a1bSJed Brown 
51c4762a1bSJed Brown    test:
52c4762a1bSJed Brown 
53c4762a1bSJed Brown    test:
54c4762a1bSJed Brown       suffix: 2
55c4762a1bSJed Brown       args: -mat_type seqbaij -mat_block_size 5
56c4762a1bSJed Brown 
57c4762a1bSJed Brown    test:
58c4762a1bSJed Brown       suffix: 3
59c4762a1bSJed Brown       args: -keep_nonzero_pattern
60c4762a1bSJed Brown 
61c4762a1bSJed Brown    test:
62c4762a1bSJed Brown       suffix: 4
63c4762a1bSJed Brown       args: -keep_nonzero_pattern -mat_type seqbaij -mat_block_size 5
64c4762a1bSJed Brown 
65c4762a1bSJed Brown TEST*/
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