blocked index sets

[Matthew Knepley]

On Wed, Aug 27, 2008 at 2:10 PM, Barry Smith <bsmith at mcs.anl.gov> wrote:
>   Even if an object (class) has NO collective operations, if, when you use
> that object, you must have partners are all
> other processes in a MPI_Comm then I think it is a good approach to have
> that be a parallel
> object that shares the comm.

I will not suggest that we go back on IS now. However, I am not sure I buy the
above argument. I see IS as just managing a list of integers, and
maybe reporting
some local properties. All the parallel actions are done by different
objects, like
Scatter or Mat. This is different from KSP or Vec which have natural
parallel actions.

   Matt

>  Barry
-- 
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