On Jun 14, 2011, at 6:04 PM, Jed Brown wrote:
> On Wed, Jun 15, 2011 at 00:10, Barry Smith <bsmith at mcs.anl.gov> wrote:
>
> It turns out that this is hard to test because Stokes problems usually have
> mixed spaces of some sort. The collocated methods are generally not robust.
> We currently have rather poor support for staggered grids, so constructing
> reasonable grid hierarchies is still a lot of user effort. I don't know of a
> simple way to fix this using DMDA. This is part of a larger issue of
> constructing custom interpolants, which doesn't seem easy at present.
>
It seems we should provide a DMSDA that is built specifically for staggered
grids, with the correct number of "slots" in the correct "locations", it would
have appropriate grid hierarchies and interpolation/restriction. Not terribly
hard but a bit of basic plumbing code. I would rather have this then try to
"tack on" the current DA a bunch more stuff.
Barry
