<div dir="ltr"><div class="gmail_default" style="font-size:small">Matt,</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">That really makes sense to me.</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">Thanks,<br>Paul</div></div><div class="gmail_extra"><br clear="all"><div><div class="gmail_signature"><div style="color:rgb(0,0,0)"><font size="1">Huaibao (Paul) Zhang<br><b><i>Gas Surface Interactions Lab</i></b><br></font></div>
<div style="color:rgb(0,0,0)"><font size="1">Department of Mechanical Engineering</font></div>
<div style="color:rgb(0,0,0)"><font size="1">University of Kentucky,</font></div>
<div style="color:rgb(0,0,0)"><font size="1">Lexington,</font></div>
<div style="margin:0px;font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;line-height:normal;font-size-adjust:none;font-stretch:normal"><font size="1">KY, 40506-0503<b><br>Office</b>: 216 Ralph G. Anderson Building<br><b>Web</b>:<a href="http://gsil.engineering.uky.edu" target="_blank"><span style="color:rgb(0,0,153)">gsil.engineering.uky.edu</span></a></font><span style="color:rgb(0,0,0)"><span style="color:rgb(0,0,153)"></span></span></div><div style="color:rgb(255,102,102)"><font size="1"><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;font-style:normal;font-weight:normal;line-height:normal;border-collapse:separate;text-transform:none;white-space:normal;font-family:Helvetica;word-spacing:0px"><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;font-style:normal;font-weight:normal;line-height:normal;border-collapse:separate;text-transform:none;white-space:normal;font-family:Helvetica;word-spacing:0px"><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;font-style:normal;font-weight:normal;line-height:normal;border-collapse:separate;text-transform:none;white-space:normal;font-family:Helvetica;word-spacing:0px"><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;font-style:normal;font-weight:normal;line-height:normal;border-collapse:separate;text-transform:none;white-space:normal;font-family:Helvetica;word-spacing:0px"><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;font-style:normal;font-weight:normal;line-height:normal;border-collapse:separate;text-transform:none;white-space:normal;font-family:Helvetica;word-spacing:0px"><span style="font-family:Tahoma"><span style="font-family:Verdana"><font face="Helvetica"><span></span></font></span></span></span></span></span></span></span></font></div></div></div>
<br><div class="gmail_quote">On Fri, Apr 17, 2015 at 9:31 AM, Matthew Knepley <span dir="ltr"><<a href="mailto:knepley@gmail.com" target="_blank">knepley@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote"><span class="">On Fri, Apr 17, 2015 at 8:28 AM, paul zhang <span dir="ltr"><<a href="mailto:paulhuaizhang@gmail.com" target="_blank">paulhuaizhang@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div style="font-size:small"><div style="font-size:12.727272033691406px">I agree with you. The performance indeed depends on the type of problem. Anyway, back to the questions I proposed, I am afraid ILU and LU are not sequential only. Am I right?</div></div></div></blockquote><div><br></div></span><div>As it says in the table, the PETSc implementations are sequential, but there are parallel implementations available through</div><div>other packages, such as SuperLU_dist, which can de downloaded through configure, e.g. --download-superlu_dist.</div><div><br></div><div>  Thanks,</div><div><br></div><div>    Matt</div><div><div class="h5"><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div style="font-size:small"><div style="font-size:12.727272033691406px">Thanks,<br>Paul</div></div></div><div class="gmail_extra"><br clear="all"><div><div><div style="color:rgb(0,0,0)"><font size="1">Huaibao (Paul) Zhang<br><b><i>Gas Surface Interactions Lab</i></b><br></font></div>
<div style="color:rgb(0,0,0)"><font size="1">Department of Mechanical Engineering</font></div>
<div style="color:rgb(0,0,0)"><font size="1">University of Kentucky,</font></div>
<div style="color:rgb(0,0,0)"><font size="1">Lexington,</font></div>
<div style="margin:0px;font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;line-height:normal;font-size-adjust:none;font-stretch:normal"><font size="1">KY, 40506-0503<b><br>Office</b>: 216 Ralph G. Anderson Building<br><b>Web</b>:<a href="http://gsil.engineering.uky.edu" target="_blank"><span style="color:rgb(0,0,153)">gsil.engineering.uky.edu</span></a></font><span style="color:rgb(0,0,0)"><span style="color:rgb(0,0,153)"></span></span></div><div style="color:rgb(255,102,102)"><font size="1"><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;font-style:normal;font-weight:normal;line-height:normal;border-collapse:separate;text-transform:none;white-space:normal;font-family:Helvetica;word-spacing:0px"><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;font-style:normal;font-weight:normal;line-height:normal;border-collapse:separate;text-transform:none;white-space:normal;font-family:Helvetica;word-spacing:0px"><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;font-style:normal;font-weight:normal;line-height:normal;border-collapse:separate;text-transform:none;white-space:normal;font-family:Helvetica;word-spacing:0px"><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;font-style:normal;font-weight:normal;line-height:normal;border-collapse:separate;text-transform:none;white-space:normal;font-family:Helvetica;word-spacing:0px"><span style="text-indent:0px;letter-spacing:normal;font-variant:normal;font-style:normal;font-weight:normal;line-height:normal;border-collapse:separate;text-transform:none;white-space:normal;font-family:Helvetica;word-spacing:0px"><span style="font-family:Tahoma"><span style="font-family:Verdana"><font face="Helvetica"><span></span></font></span></span></span></span></span></span></span></font></div></div></div>
<br><div class="gmail_quote">On Fri, Apr 17, 2015 at 3:22 AM, Patrick Sanan <span dir="ltr"><<a href="mailto:patrick.sanan@gmail.com" target="_blank">patrick.sanan@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="auto"><div>You can find the current list of preconditioners on line 40 here:</div><div><br></div><div><a href="http://www.mcs.anl.gov/petsc/petsc-current/include/petscpc.h.html" target="_blank">http://www.mcs.anl.gov/petsc/petsc-current/include/petscpc.h.html</a></div><div><br></div><div>You can click on the names to be taken to man pages.</div><div><br></div><div>However, since preconditioners are by nature problem-dependent, it's a better idea to try to look up what might be an appropriate preconditioner for your system and then see how to use PETSc to apply it. There's a high probability that what you need is supported either natively by PETSc or as Jed's note demonstrates, through interfaces to external libraries (of which there are a large number - run ./configure -help to get an idea of the options available and the configure flags to use them)<br><br></div><div><div><div><br>Il giorno 16/apr/2015, alle ore 23:54, huaibao zhang <<a href="mailto:huaibao.zhang@gmail.com" target="_blank">huaibao.zhang@gmail.com</a>> ha scritto:<br><br></div><blockquote type="cite"><div><div>Hello there,</div><div><br></div><div>I have been confused of the extent of the available preconditioners in PETSc for a while. Here are the lists I got from one slide of a lecture notes saying</div><div><br></div><div>Block Jacobi,</div><div>Jacobi,</div><div>Overlapping Additive Schwarz,</div><div>ICC, ILU (sequential only)</div><div>ILU(K), LU(direct solver, sequential only)</div><div>sor</div><div>etc.</div><div><br></div><div><br></div><div>But in some other sources, only LU is highlighted with "sequential only". Which one is correct? I am using MATCreateAIJ to construct my A. Which preconditioner is available to me? By the way, I  tested asm, ilu, icc, and they all failed. </div><div><br></div><div>Thanks,</div><div>Paul</div><div><div style="color:rgb(0,0,0);letter-spacing:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;word-wrap:break-word"><div style="color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:-webkit-auto;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;word-wrap:break-word"><div style="color:rgb(0,0,0);font-family:Helvetica;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:-webkit-auto;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px;word-wrap:break-word"><div><font size="1"><br></font></div></div></div></div></div></div></blockquote></div></div></div></blockquote></div><br></div>
</blockquote></div></div></div><span class="HOEnZb"><font color="#888888"><br><br clear="all"><div><br></div>-- <br><div>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</div>
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