In place ILU(0) factorization

[Laslo Tibor Diosady]

Hi,

I wanted to perform an in place ILU factorization with fill level of 0 (ie 
ILU(0)) for a SeqBAIJ matrix. This works fine when I use a natural 
ordering however when I try to use a different matrix reordering I get the 
following error.

[0]PETSC ERROR: MatILUFactor_SeqBAIJ() line 1768 in 
src/mat/impls/baij/seq/baij.c
[0]PETSC ERROR: Invalid argument!
[0]PETSC ERROR: Row and column permutations must be identity for in-place 
ILU!
[0]PETSC ERROR: MatILUFactor() line 2107 in src/mat/interface/matrix.c

In otherwords, Petsc only supports in place ILU(0) without reordering.

The idea behind doing an in place factorization is so that I don't use 
twice as much memory to store my matrix (ie the original matrix and the 
ILU factored matrix).


Is in place ILU factorization with reordering going to be supported by 
Petsc anytime in the near future or is there an easy work around so I can 
get this to work?

Thanks,

Laslo