Barry Smith wrote: > > On Mon, 9 Apr 2007, Ben Tay wrote: >> 3. why can't I use bcgs or bicg with hypre? > > hypre doesn't support applying the transpose of the preconditioner that > bcgs and bicg need? I don't believe that Bi-CGSTAB (-ksp_type bcgs) uses matrix or preconditioner transposes. On the other hand, bicg does. -- Boyce