On Mon, Dec 12, 2011 at 3:10 AM, Alexander Grayver <span dir="ltr"><<a href="mailto:agrayver@gfz-potsdam.de">agrayver@gfz-potsdam.de</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Hi Barry,<br>
<br>
Thanks for answer. I should have asked about that from the very beginning actually.<br>
I get 2 times decrease in performance with 20 RHS, I can imagine how slow it will be when I will use thousands of them,<br>
moreover it will require a lot of memory to store them as a dense matrix.<br>
<br>
On 11.12.2011 18:50, Barry Smith wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
On Dec 11, 2011, at 9:29 AM, Alexander Grayver wrote:<br>
One by one<br>
</blockquote>
<br>
I'm wondering why? All main direct packages like MUMPS, SuperLU_DIST, PaSTiX support multiple RHS.<br></blockquote><div><br></div><div>We don't need it for the vast majority of problems.</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
We do not handle a sparse right hand side.</blockquote></blockquote><div><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Since I already transferred my code to PETSc anyway, my question now if it's possible to implement sparse multiple RHS and solve them simultaneously?<br>
Something like MatMatSolveSparse. I would implement it myself, the question is there a way to integrate it into PETSc as a patch or something like that?<br></blockquote><div><br></div><div>You can just implement MatMatSolve for another matrix type, like AIJ (although you probably want the transpose).</div>
<div><br></div><div> Matt</div><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
Regards,<br>
Alexander<br>
</blockquote></div><br><br clear="all"><div><br></div>-- <br>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>
-- Norbert Wiener<br>