[petsc-users] MATNEST with shell matrices

[Boyce Griffith]

On 2/21/13 7:04 PM, Jed Brown wrote:
>
> On Thu, Feb 21, 2013 at 5:59 PM, Boyce Griffith <griffith at cims.nyu.edu
> <mailto:griffith at cims.nyu.edu>> wrote:
>
>     There is no such thing as an IS for these data structures in the
>     current implementation.
>
>
>
> But there is a local and global size. (You had to pick something to
> create the Vec.) Therefore, the global space is _defined_ as the
> concatenation of all those contiguous local spaces. You need not store
> it that way, but the abstract space exists. If you use interfaces that
> ask for ISs, they will be with respect to that abstract space.

Ah, I think I wasn't clear about what I mean here by "wrapper".

Basically, we have a subclass of Vec that knows how to evaluate vector 
space operations using the "wrapped" SAMRAI data.  For instance, there 
is no VecGetArray().

-- Boyce