[petsc-users] zeros in sparse aij

Satish Balay balay at mcs.anl.gov
Wed Dec 7 10:53:29 CST 2011


On Wed, 7 Dec 2011, Xiangdong Liang wrote:

> I think I did have 10 zeros entries. In my script, I have inserted
> zeros by MatSetValue(A,i, (i+1)%N, 0.0, ADD_VALUES); Why doesn't that
> option matter in my case? That option prevents PETSc from inserting
> zeros, doesn't it? Thank you.

MatSetValue is a macro - perhaps its not processing the above properly.

Try:

PetscScalar zero=0.0
MatSetValue(A,i, (i+1)%N, zero, ADD_VALUES)

And if its still not inzerting these zeros - check in a debugger.

Satish


More information about the petsc-users mailing list