[petsc-users] Using DMDA with regular matrices

[Yuyun Yang]

Hello team,

Hope you're staying healthy amid the coronavirus craziness.

Just want to ask a basic question: if my grid is managed by DMDA, then do 
matrices in all my intermediate steps have to be compatible with DMDA and 
formed in a special way, or can I just form them as usual (i.e. do MatCreate, 
MatMPIAIJSetPreallocation, MatSetValue etc.)? Asking this because I'm using a 
mix of matrix-free and matrix-based operations, and MatShell seems to require 
the use of DMDA.

Thanks for your help.

Best,
Yuyun