[petsc-users] Clarification on PCASMSetLocalSubdomain is and is_local

[Luc Berger-Vergiat]

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?

-- 
Best,
Luc