Question regarding PCMG

[Matthew Knepley]

On 8/13/07, TsuyoshiKoyama(berkeley) <tkoyama at berkeley.edu> wrote:
> As for the second case, the reason I might not select a coarse solver is
> since I
> am trying to solve a Helmholtz equation and the coarse grid solve might not
> be
> correct enough to apply. Thus, you may just point out that the coarse grid
> should
> be large enough to resolve the so called low frequency error and that if you
> do so
> you should still be able to solve direct, but I was curious on testing
> different types
> of operations at the coarsest level.

The coarse solver can be set to anything you choose. You just extract the
coarse KSP and set the type.

  Thanks,

    Matt

-- 
What most experimenters take for granted before they begin their
experiments is infinitely more interesting than any results to which
their experiments lead.
-- Norbert Wiener