On Thu, Oct 8, 2009 at 3:21 PM, Matt Funk <span dir="ltr"><<a href="mailto:mafunk@nmsu.edu">mafunk@nmsu.edu</a>></span> wrote:<br><div class="gmail_quote"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div style="font-family: 'Arial'; font-size: 12pt; font-weight: 400; font-style: normal;">Hi,<br>
<p style="margin: 0px; text-indent: 0px;"><br></p>i was wondering if i can get some advice on how to use the DA objec tin PETSC. <br>
<p style="margin: 0px; text-indent: 0px;"><br></p>Is it possible to create a DA object by inserting a set of boxes into it? Or can the DA object only be used based on a single rectangular box?<br>
</div></blockquote><div><br>A DA is a single rectangular prism. You could choose not to assign equations to some vertices, or to put the identity there.<br><br> Matt<br> </div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div style="font-family: 'Arial'; font-size: 12pt; font-weight: 400; font-style: normal;">say my domain has 2 boxes:<br>
1) (0,0) - (64,64) <br>
2) (64,64) - (128,128)<br>
<p style="margin: 0px; text-indent: 0px;"><br></p>Can i "register" those 2 boxes with the object?<br>
<p style="margin: 0px; text-indent: 0px;"><br></p>If that is possible, then is it valid if certain cells/nodes of these boxes overlap? say they both contain cell/node (64,64)?<br>
<p style="margin: 0px; text-indent: 0px;"><br></p><p style="margin: 0px; text-indent: 0px;"><br></p>If that is possible, and i run in parallel, will the solution on cell/node (64,64) be returned to both processes (the first owning box1 and the second box2).<br>
<p style="margin: 0px; text-indent: 0px;"><br></p><p style="margin: 0px; text-indent: 0px;"><br></p>Right now i am building my matrix 'by hand' and i believe the mentioned "overlap" is causing an ill-conditioned matrix (as addressed earlier in this list), even through the values on the overlapping nodes are the same.<br>
<p style="margin: 0px; text-indent: 0px;"><br></p><p style="margin: 0px; text-indent: 0px;"><br></p>thanks<br><font color="#888888">
matt<br>
<p style="margin: 0px; text-indent: 0px;"><br></p><p style="margin: 0px; text-indent: 0px;"><br></p></font></div></blockquote></div><br><br clear="all"><br>-- <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>