[petsc-dev] attaching field information to PetscLayout?

[Barry Smith]

On May 14, 2011, at 3:25 PM, Jed Brown wrote:

> On Sat, May 14, 2011 at 22:21, Barry Smith <bsmith at mcs.anl.gov> wrote:
> The user will be composing preconditioners on splits etc using the string name (you cannot type an IS at the command line but you can type "pressure") so I am not sure why you are so focused on "the IS _is_ the thing you need". So I can see the string names as being important.
> 
> I assumed fieldsplit would use the string name and then hold onto the IS (there is a good chance it is needed internally anyway). I don't see why the string name would be needed in a performance-sensitive place since it's only for "configuration" anyway.

  So long as that can be managed, and you believe it can, then there would be no need to also have "naming by number" which you wish to avoid.  I tend to agree with you thatt should be doable so we don't need any "naming by number".


    Barry