[petsc-users] How to use MAT_SCHUR_COMPLEMENT_AINV_BLOCK_DIAG

[Tang, Qi]

Hi,
What’s the meaning of MAT_SCHUR_COMPLEMENT_AINV_BLOCK_DIAG?

Form the inversion of diagonal blocks first and then do matrix multiplication 
to get a Schur complement? Is that a feasible option in practice?

Qi