Ok I get it, then if I have multiple subdomains on the local processor
is and is_local will be arrays of is that represent each subdomain on
that processor?
Best,
Luc
On 06/02/2016 06:21 PM, Matthew Knepley wrote:
On Thu, Jun 2, 2016 at 5:11 PM, Luc Berger-Vergiat
<lb2...@columbia.edu <mailto:lb2...@columbia.edu>> wrote:
Hi all,
I would like a quick clarification on what is and is_local are
representing in the PCASMSetLocalSubdomains().
My understanding is that if I have two mpi ranks and four
subdomains I can end up having four blocks that I can denote as
follows:
| domain1 | domain2 | domain3 | domain3 |
rank1 | block11 | block12 | block13 | |
rank2 | block21 | block22 | -- | block24 |
to each blockIJ I associate isIJ.
So for rank1 I will have is=[1,2,3] and is_local=[is11,is12,is13],
and for rank2 I will have is=[1,2,4] and is_local=[is21,is22,is24].
Or am I not understanding things correctly?
I did not understand the above.
The best way to think of this is algebraically. Suppose you have a
matrix A, and you divide the rows into k disjoint sets where each
process gets one set. Then is_local on each process is a list of the
rows in that set. Now we also allow some overlap, which means
rows in other sets are also used. The is on each process contains both
is_local and these extra rows from other sets.
Thanks,
Matt
--
Best,
Luc
--
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
--
Best,
Luc
