<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Wed, Feb 11, 2015 at 2:07 PM, Hanglin Ye <span dir="ltr"><<a href="mailto:hanglinye@gmail.com" target="_blank">hanglinye@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>Hi,<br>Thank you again for the reply. I am trying to run ex62. But there is an error : "Mesh generation needs external package support. Please reconfigure with --download-triangle." I then configure again with --download triangle, and it is download and installed. But this error keeps showing up. Could you please let me know if I am missing anything?<br></div></div></blockquote><div><br></div><div>Always send the entire error text. It will show your configure line, and lots of other information.</div><div><br></div><div> Thanks,</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"><div dir="ltr">Thank you.<br></div><div class="gmail_extra"><br><div class="gmail_quote">On Wed, Feb 11, 2015 at 1:05 PM, 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>On Wed, Feb 11, 2015 at 12:01 PM, Hanglin Ye <span dir="ltr"><<a href="mailto:hanglinye@gmail.com" target="_blank">hanglinye@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 dir="auto"><div>Thank you very much for the reply. <br><br>I am not very sure if structured/unstructured mesh means differently in PETSc, but my mesh are simply hexahedral mesh, which I assume is structured. Is there any difference when dealing with structured and unstructured mesh?<br></div></div></div></blockquote><div> <br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div dir="auto"><div>And another question is: Can I say that I only need to provide the whole domain, and PETSc can take care of the decomposition, so that I do not need to use software such as Metis to partition the mesh in advance?<br></div></div></div></blockquote><div><br></div></span><div>Now your mesh sounds unstructured. SNES ex62 is an example of a finite element code using DMPlex</div><div>which can have tetrahedral or hexahedral cells, and solves Stokes equation.</div><div><br></div><div>PETSc can handle partitioning and distribution for you.</div><div><br></div><div> Thanks,</div><div><br></div><div> Matt</div><span><div> </div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div dir="auto"><div></div><div>Thank you. <br></div><div><br></div><div><br>On Feb 11, 2015, at 12:01, Matthew Knepley <<a href="mailto:knepley@gmail.com" target="_blank">knepley@gmail.com</a>> wrote:<br><br></div><blockquote type="cite"><div><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Wed, Feb 11, 2015 at 10:52 AM, Hanglin Ye <span dir="ltr"><<a href="mailto:hanglinye@gmail.com" target="_blank">hanglinye@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><div>Dear all,<br><br></div>I am new to PETSc and I want to use it to parallel my current serial FEM code. I want to use Domain Decomposition Method so that the whole FEM domain is partitioned into sub-domains and computations are performed in sub-domains then assemble together. Is there a way to use PETSc to realize that ? <br><br></div>I've been searching through tutorials but none seems to be clear about this aspect. I mainly wish to know what solver of PETSc do I need. </div></blockquote><div><br></div><div>Do you have a structured or unstructured mesh? In either case, you will use a DM to encapsulate your mesh, which will give you</div><div>DMLocalToGlobal() and DMGlobalToLocal() to map between Vecs which are appropriate for the solver (global) and those with</div><div>ghost regions which are appropriate for assembly (local). You can see an example in SNES ex5, ex12, and ex19.</div><div><br></div><div> Thanks,</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"><div dir="ltr"><div><div><div>Thank you very much.<span><font color="#888888"><span><font color="#888888"><br></font></span></font></span></div><span><font color="#888888"><span><font color="#888888"><div>-- <br><div><div dir="ltr">Hanglin Ye<br>Ph.D.Student MANE, RPI<br></div></div>
</div></font></span></font></span></div></div></div><span><font color="#888888">
</font></span></blockquote></div><span><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>
</font></span></div></div>
</div></blockquote></div></div>
</blockquote></span></div><span><br><br clear="all"><span class="HOEnZb"><font color="#888888"><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>
</font></span></span></div></div><span class="HOEnZb"><font color="#888888">
</font></span></blockquote></div><span class="HOEnZb"><font color="#888888"><br><br clear="all"><br>-- <br><div><div dir="ltr">Hanglin Ye<br>Ph.D.Student MANE, RPI<br></div></div>
</font></span></div>
</blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature">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>
</div></div>