1 2 #include <petscmat.h> 3 4 int main(int argc,char **argv) 5 { 6 Mat A, B; 7 const char *pfx; 8 9 PetscCall(PetscInitialize(&argc, &argv, NULL, NULL)); 10 PetscCall(MatCreate(PETSC_COMM_WORLD, &A)); 11 PetscCall(MatSetSizes(A, 1, 1, PETSC_DECIDE, PETSC_DECIDE)); 12 PetscCall(MatSetUp(A)); 13 PetscCall(MatSetOptionsPrefix(A, "foo_")); 14 PetscCall(MatGetDiagonalBlock(A, &B)); 15 /* Test set options prefix with the string obtained from get options prefix */ 16 PetscCall(PetscObjectGetOptionsPrefix((PetscObject)A,&pfx)); 17 PetscCall(MatSetOptionsPrefix(B, pfx)); 18 PetscCall(MatDestroy(&A)); 19 20 PetscCall(PetscFinalize()); 21 return 0; 22 } 23 24 /*TEST 25 26 test: 27 28 TEST*/ 29