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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This is exactly not a PETSc question. I am solving a Poisson equation using finite elements. I would like to impose PBC. I am thinking of using the Lagrange multiplier method to impose them as constraints. Or do you think I could take an
alternative approach?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you for your help.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Kind regards,<o:p></o:p></p>
<p class="MsoNormal">Karthik.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><span style="mso-ligatures:none;mso-fareast-language:EN-GB">-- <o:p></o:p></span></p>
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<p class="MsoNormal"><b><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#2D2D62;mso-ligatures:none;mso-fareast-language:EN-GB">Dr. Karthik Chockalingam</span></b><span style="color:#212121;mso-ligatures:none;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#414141;mso-ligatures:none;mso-fareast-language:EN-GB">High Performance Software Engineering Group</span><span style="color:#212121;mso-ligatures:none;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#414141;mso-ligatures:none;mso-fareast-language:EN-GB">Hartree Centre | Science and Technology Facilities Council</span><span style="color:#212121;mso-ligatures:none;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#212121;mso-ligatures:none;mso-fareast-language:EN-GB"><a href="mailto:karthikeyan.chockalingam@stfc.ac.uk"><span style="color:#0563C1">karthikeyan.chockalingam@stfc.ac.uk</span></a></span><span style="color:#212121;mso-ligatures:none;mso-fareast-language:EN-GB"><o:p></o:p></span></p>
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