[petsc-users] Use block Jacobi preconditioner with SNES

[Ali Reza Khaz'ali]

> The BAIJ blocks are usually grouping of fields for each discretization
> "point".  NEST is usually grouping different fields with which you want
> to use different sparse solution strategies (e.g., algebraic multigrid
> on some, a simpler solver on others).
>
I have to apologize for taking so much of your time. I'd be grateful if 
you could kindly answer my (hopefully last) question: what do you 
propose for a non-linear system that has variable number of unknowns in 
each of its discretization points?

Many thanks,
Ali