On Thu, 22 Apr 2010 14:07:06 -0500, Barry Smith <bsmith at mcs.anl.gov> wrote: > > I don't understand how knowing the preallocation for SBAIJ give you > an efficient way to know the preallocation for BAIJ? Say you have > 20,000 processors can you efficiently get the information where it is > needed? Are you willing to write the code to do that?
Ah, you're right, there's no way to preallocate BAIJ from SBAIJ without indices (it's not just hard, there isn't enough information). That seems to have been a bad example. But there is a clear way to preallocate AIJ from BAIJ and that code is written (in SlicedGetMatrix(), if not elsewhere). So what about having AIJ implement BAIJ preallocation, consistent with the theme of BAIJ interfaces merely providing more structured information? Jed
