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<div>Are your matrices dense?</div>
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<div style="FONT-SIZE: 13px; FONT-FAMILY: Tahoma">Peter G. Raeth<a></a>, Ph.D.<br>
Senior Staff Scientist<br>
Signal and Image Processing<br>
High Performance Technologies, Inc<br>
937-904-5147<br>
<a href="mailto:praeth@hpti.com" target="_blank">praeth@hpti.com</a><a></a>
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<div id="divRpF847206" style="DIRECTION: ltr"><font face="Tahoma" color="#000000" size="2"><b>From:</b> petsc-users-bounces@mcs.anl.gov [petsc-users-bounces@mcs.anl.gov] on behalf of RenZhengYong [renzhengyong@gmail.com]<br>
<b>Sent:</b> Thursday, January 06, 2011 1:18 PM<br>
<b>To:</b> PETSc users list<br>
<b>Subject:</b> Re: [petsc-users] PETSc and dense matrices<br>
</font><br>
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<div>Hi, Hamid,<br>
I am also using BEM to solve 3D EM problems.<br>
But I only am using the PETSc on one machine. <br>
<br>
Kind regards,<br>
Zhengyong<br>
<br>
<div class="gmail_quote">On Thu, Jan 6, 2011 at 6:46 PM, Hamid M. <span dir="ltr">
<<a href="mailto:spam.wax@gmail.com" target="_blank">spam.wax@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">
Hello,<br>
<br>
In our research, we solve the diffusion equation PDE using Boundary<br>
Element Method (BEM).<br>
I am trying to parallelize the code we already have and I was<br>
wondering if PETSc is the right tool for us.<br>
<br>
As you know, BEM produces a dense LHS matrix that needs to be solved.<br>
Also due to the size of our problems, populating the entities of the<br>
LHS matrix needs to be done on different processes as it won't fit on<br>
a single process of our cluster.<br>
<br>
So I was wondering if you guys can answer my questions:<br>
<br>
1- Can I use PETSc to build/populate my LHS matrix on different nodes<br>
of a cluster (as opposed to constructing it on a single node and then<br>
distributing it) ?<br>
<br>
2- Are there optimized parallel solvers for dense matrices in PETSc ?<br>
<br>
3- If the answer to question 1 is 'No', can I build my LHS matrix<br>
independent of PETSc and then direct PETSc to solve it for me ?<br>
<br>
thanks in advance,<br>
<font color="#888888"><br>
Hamid<br>
</font></blockquote>
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<br>
-- <br>
Zhengyong Ren<br>
AUG Group, Institute of Geophysics<br>
Department of Geosciences, ETH Zurich<br>
NO H 47 Sonneggstrasse 5<br>
CH-8092, Zürich, Switzerland<br>
Tel: +41 44 633 37561<br>
e-mail: <a href="mailto:zhengyong.ren@aug.ig.erdw.ethz.ch" target="_blank">zhengyong.ren@aug.ig.erdw.ethz.ch</a><br>
Gmail: <a href="mailto:renzhengyong@gmail.com" target="_blank">renzhengyong@gmail.com</a><br>
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