[petsc-users] How can I retrieve the IS for all Missing Diagonal entries?

[Eric Chamberland]

Hi,

I have 2 questions:

First, I am looking for a function that is almost like 
MatMissingDiagonal, but that would return me *all* missing diagonal entries.

Does it exists?

If not, is there another way of doing this?

Second: after searching through Petsc list, I found this that upset me a 
bit:

https://www.mail-archive.com/petsc-users@mcs.anl.gov/msg22867.html

so maybe I should modify our code to be fully compliant with this?  I 
have some examples (MUMPS) that are working without diagonal entries but 
I didn't tried other PCs or KSPs...

Thanks,

Eric