<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<meta name="Generator" content="Microsoft Word 15 (filtered medium)">
<style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0cm;
font-size:11.0pt;
font-family:"Calibri",sans-serif;
mso-fareast-language:EN-US;}
span.EmailStyle17
{mso-style-type:personal-compose;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-family:"Calibri",sans-serif;
mso-fareast-language:EN-US;}
@page WordSection1
{size:612.0pt 792.0pt;
margin:72.0pt 72.0pt 72.0pt 72.0pt;}
div.WordSection1
{page:WordSection1;}
/* List Definitions */
@list l0
{mso-list-id:1387874079;
mso-list-type:hybrid;
mso-list-template-ids:-1254583294 134807567 134807577 134807579 134807567 134807577 134807579 134807567 134807577 134807579;}
@list l0:level1
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-18.0pt;}
@list l0:level2
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-18.0pt;}
@list l0:level3
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l0:level4
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-18.0pt;}
@list l0:level5
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-18.0pt;}
@list l0:level6
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l0:level7
{mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-18.0pt;}
@list l0:level8
{mso-level-number-format:alpha-lower;
mso-level-tab-stop:none;
mso-level-number-position:left;
text-indent:-18.0pt;}
@list l0:level9
{mso-level-number-format:roman-lower;
mso-level-tab-stop:none;
mso-level-number-position:right;
text-indent:-9.0pt;}
@list l1
{mso-list-id:1845246448;
mso-list-template-ids:-287656314;}
ol
{margin-bottom:0cm;}
ul
{margin-bottom:0cm;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]-->
</head>
<body lang="EN-GB" link="#0563C1" vlink="#954F72" style="word-wrap:break-word">
<div class="WordSection1">
<p class="MsoNormal"><span style="color:#0E101A;mso-fareast-language:EN-GB">Hello PETSc users,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0E101A;mso-fareast-language:EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#0E101A;mso-fareast-language:EN-GB">Thank you for this very active community of users and the mailing list.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0E101A;mso-fareast-language:EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#0E101A;mso-fareast-language:EN-GB">I am looking for a PETSc example which solves the Poisson equation on a 2D domain using FEM (or HO-FEM if possible). I would like the following:<o:p></o:p></span></p>
<ol style="margin-top:0cm" start="1" type="1">
<li class="MsoNormal" style="color:#0E101A;mso-list:l1 level1 lfo2"><span style="mso-fareast-language:EN-GB">The example should be formulated fully on PETSc, and to be solved with KSP objects in PETSc.<o:p></o:p></span></li><li class="MsoNormal" style="color:#0E101A;mso-list:l1 level1 lfo2"><span style="mso-fareast-language:EN-GB">The problem should scale up to a few hundred processors (ideally 1000 procs).<o:p></o:p></span></li><li class="MsoNormal" style="color:#0E101A;mso-list:l1 level1 lfo2"><span style="mso-fareast-language:EN-GB">Ideally on a unit square with either Square or Triangle element discretization.<o:p></o:p></span></li><li class="MsoNormal" style="color:#0E101A;mso-list:l1 level1 lfo2"><span style="mso-fareast-language:EN-GB">There should be an option to specify Dirichlet/Neumann-type BCs on the boundaries.<o:p></o:p></span></li></ol>
<p class="MsoNormal"><span style="color:#0E101A;mso-fareast-language:EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#0E101A;mso-fareast-language:EN-GB">I was wondering if someone could point me to such an example as I am relatively new to PETSc – and I am trying to avoid reinventing the wheel. I have had a look at Examples 29,32,50
and 66 in the PETSc tutorials – while they are very close to what I need I am not sure if they scale to a few hundred processors. Furthermore, I am aware that I can formulate such a problem with FENICS/Firedrake with relative ease and these software interfaces
with PETSc quite well. However, I am just trying to see if such an application already exists purely in PETSc.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0E101A;mso-fareast-language:EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#0E101A;mso-fareast-language:EN-GB">Thanks, and Best<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#0E101A;mso-fareast-language:EN-GB">Parv<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
</div>
</body>
</html>