[petsc-users] No VecGetLocalSubVector?

[Garth Wells]

On Thu, 2018-03-08 at 11:25 -0700, Jed Brown wrote:
> Garth Wells <gnw20 at cam.ac.uk> writes:
> 
> > On Wed, 2018-03-07 at 16:13 -0700, Jed Brown wrote:
> > > No reason, just didn't need it.  I don't think any PETSc
> > > developers
> > > use
> > > VecSetValues* because VecScatter is a more natural interface with
> > > lower
> > > overhead.
> > > 
> > 
> > Any demos of its recommended use?
> 
> snes/examples/tutorials/ex28.c is my recommended demo for both
> MatGetLocalSubMatrix() and composite vectors.  You can follow the
> example (using DMComposite) or call VecScatter directly.

Thanks, Jed. Could you expand on VecSetValues* vs VecScatter? I'm a bit
perplexed because I can't find anything in the docs discussing use of 
VecSetValues* vs VecScatter.

Garth