[petsc-users] How does KSPSetNullSpace() work?

[Jed Brown]

On Tue, Jan 10, 2012 at 03:50, Alexander Grayver <agrayver at gfz-potsdam.de>wrote:

>
> http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/KSP/KSPSetNullSpace.html
>
> You set nullspace without any particular information:
>
> ierr = MatNullSpaceCreate(PETSC_COMM_WORLD, PETSC_TRUE, 0, PETSC_NULL,
> &nullsp);
> ierr = KSPSetNullSpace(ksp, nullsp);
>
> What does it project and how works in this case?


This removes the constant null space. The has_const argument is equivalent
to creating a constant vector (but more efficient).
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120110/07ccf31e/attachment.htm>