<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: times new roman,new york,times,serif; font-size: 12pt; color: #000000'><br>Hong,<div><br></div><div> Thanks for the suggestion of Elemental. However I need to have the dense matrix have the same parallel communicator as the sparse matrix. </div><div>If I use elemental, then the numbering changes, will I be able to multiply with the sparse matrix which has a different numbering scheme and communicator?</div><div><br></div><div>In any case I would want the resultant matrices A and M to be elemental type since I need to solve a dense eigenvalue problem.</div><div><br></div><div>Regards,</div><div>Swarnava <br><hr id="zwchr"><div style="color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"><b>From: </b>"Hong" <hzhang@mcs.anl.gov><br><b>To: </b>"Swarnava Ghosh" <sghosh2012@gatech.edu><br><b>Cc: </b>"PETSc users list" <petsc-users@mcs.anl.gov><br><b>Sent: </b>Thursday, February 5, 2015 8:22:13 PM<br><b>Subject: </b>Re: [petsc-users] Large rectangular Dense Transpose multiplication with sparse<br><br><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">Swarnava:</div><div class="gmail_quote">The matrix product A will be a dense matrix. You may consider using Elemental package for such matrix product.</div><div class="gmail_quote"><br></div><div class="gmail_quote">Hong<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><br>
Dear all,<br>
<br>
I am trying to compute matrices A = transpose(R)*H*R and M = transpose(R)*R where<br>
H is a sparse (banded) matrix in MATMPIAIJ format (5 million x 5 million total size)<br>
R is a MPI dense matrix of size 5 million x 2000.<br>
<br>
I tried 1) MatPtAP - Failed, realized this only works for pairs of AIJ matrices<br>
2) First multiplying H*R and storing in 5 million x 2000 MPI dense. Then MatTranspose of R and multiplying the transposed R with 5 million x 2000 dense. This multiplication fails.<br>
<br>
Could someone please suggest a way of doing this.<br>
<br>
Regards,<br>
Swarnava<br>
<span class="HOEnZb"><font color="#888888">--<br>
Swarnava Ghosh<br>
</font></span></blockquote></div><br></div></div>
</div><br><br><br>-- <br><div><span name="x"></span>Swarnava Ghosh<br>PhD Candidate,<br>Structural Engineering, Mechanics and Materials<br>School of Civil and Environmental Engineering<br>Georgia Institute of Technology<br>Atlanta, GA 30332<span name="x"></span><br></div></div></div></body></html>