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<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">Hi Matt,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">You mentioned it doesn’t hurt to set the smoothing flags<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"><a href="https://urldefense.us/v3/__https:/github.com/hypre-space/hypre/blob/3caa81955eb8d1b4e35d9b450e27cf6d07b50f6e/src/examples/ex15.c*L965__;Iw!!G_uCfscf7eWS!biuCOXkV-qD-e8iTXiwaD9XJ0EWuqr2PidZJdPqbnFzCshQFo-mclGSvGBOPuGSTkjPvMKnIfJzWos7QShcSitpwyrhL55yOMB-v$" target="_blank">https://github.com/hypre-space/hypre/blob/3caa81955eb8d1b4e35d9b450e27cf6d07b50f6e/src/examples/ex15.c#L965</a></span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">Do you know where I can look for the equivalent PETSc commands? Thank you.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">Kind regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US">Karthik.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;mso-fareast-language:EN-US"><o:p> </o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt"><b><span style="font-size:12.0pt;color:black">From:
</span></b><span style="font-size:12.0pt;color:black">Matthew Knepley <knepley@gmail.com><br>
<b>Date: </b>Friday, 6 September 2024 at 17:57<br>
<b>To: </b>Chockalingam, Karthikeyan (STFC,DL,HC) <karthikeyan.chockalingam@stfc.ac.uk><br>
<b>Cc: </b>petsc-users@mcs.anl.gov <petsc-users@mcs.anl.gov><br>
<b>Subject: </b>Re: [petsc-users] Hypre AMS usage<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">On Fri, Sep 6, 2024 at 11:37</span><span style="font-size:12.0pt;font-family:"Arial",sans-serif"> </span><span style="font-size:12.0pt">AM Karthikeyan Chockalingam - STFC UKRI via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a>>
wrote:<o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt">Hello,</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt">I am trying to use the Hypre AMS preconditioner for the first time.
</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt">I am following the example problem from Hypre</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"><a href="https://urldefense.us/v3/__https:/github.com/hypre-space/hypre/blob/3caa81955eb8d1b4e35d9b450e27cf6d07b50f6e/src/examples/ex15.c*L954__;Iw!!G_uCfscf7eWS!biuCOXkV-qD-e8iTXiwaD9XJ0EWuqr2PidZJdPqbnFzCshQFo-mclGSvGBOPuGSTkjPvMKnIfJzWos7QShcSitpwyrhL5ySgA0XM$" target="_blank">https://github.com/hypre-space/hypre/blob/3caa81955eb8d1b4e35d9b450e27cf6d07b50f6e/src/examples/ex15.c#L954</a></span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt">I have so far successfully set the discrete gradient operator and vertex co-ordinates,</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt">// Set discrete gradient
</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> petscErr = PCHYPRESetDiscreteGradient(pc, par_G);</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> // Set vertex coordinates</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> petscErr = PCHYPRESetEdgeConstantVectors(pc, par_xvec, par_yvec, par_zvec);</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt">Do I need to set the following smoothing options?</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"><a href="https://urldefense.us/v3/__https:/github.com/hypre-space/hypre/blob/3caa81955eb8d1b4e35d9b450e27cf6d07b50f6e/src/examples/ex15.c*L965__;Iw!!G_uCfscf7eWS!biuCOXkV-qD-e8iTXiwaD9XJ0EWuqr2PidZJdPqbnFzCshQFo-mclGSvGBOPuGSTkjPvMKnIfJzWos7QShcSitpwyrhL55yOMB-v$" target="_blank">https://github.com/hypre-space/hypre/blob/3caa81955eb8d1b4e35d9b450e27cf6d07b50f6e/src/examples/ex15.c#L965</a></span><span style="font-size:12.0pt"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">It cannot hurt. I would set them to begin with.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"> <o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt">Also, do I need to convert from MATMPIAIJ to CSR?</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"><a href="https://urldefense.us/v3/__https:/github.com/hypre-space/hypre/blob/3caa81955eb8d1b4e35d9b450e27cf6d07b50f6e/src/examples/ex15.c*L984__;Iw!!G_uCfscf7eWS!biuCOXkV-qD-e8iTXiwaD9XJ0EWuqr2PidZJdPqbnFzCshQFo-mclGSvGBOPuGSTkjPvMKnIfJzWos7QShcSitpwyrhL53Trv1si$" target="_blank">https://github.com/hypre-space/hypre/blob/3caa81955eb8d1b4e35d9b450e27cf6d07b50f6e/src/examples/ex15.c#L984</a></span><span style="font-size:12.0pt"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">No.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"> <o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt">What are the other PETSc calls to invoke AMS? Is there an example problem I can look at?</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt">I do not know. I don't think we have an example.<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"> Thanks,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"> Matt<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"> <o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt">Thank you.</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt">Karthik.</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt"> </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">-- </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#2D2D62">Karthik Chockalingam, Ph.D.</span></b><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:black">Senior Research Software Engineer</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:black">High Performance Systems Engineering Group</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:black">Hartree Centre | Science and Technology Facilities Council</span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#212121"><a href="mailto:karthikeyan.chockalingam@stfc.ac.uk" target="_blank"><span style="color:#0563C1">karthikeyan.chockalingam@stfc.ac.uk</span></a></span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:black"> </span><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#414141"> </span><span style="font-size:12.0pt"><o:p></o:p></span></p>
<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><b><span style="font-size:10.5pt;font-family:"Arial",sans-serif;color:#414141"> </span></b><span style="font-size:12.0pt;font-family:"Times New Roman",serif;color:#1F497D"><img border="0" width="254" height="116" style="width:2.6458in;height:1.2083in" id="m_-9159410701733724734Picture_x0020_1" src="cid:ii_191c843d0a64cff311" alt="signature_3970890138"></span><span style="font-size:12.0pt"><o:p></o:p></span></p>
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<p class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span style="font-size:12.0pt"> <o:p></o:p></span></p>
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<o:p></o:p></span></p>
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<p class="MsoNormal"><span class="gmailsignatureprefix"><span style="font-size:12.0pt">--
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<p class="MsoNormal"><span style="font-size:12.0pt">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<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:12.0pt"><a href="https://urldefense.us/v3/__http://www.cse.buffalo.edu/*knepley/__;fg!!G_uCfscf7eWS!ab7xBNMnurfBQihWzSOZdJKuuhPObxZolYSuACYpW4-NN7L84moQXv7vO962vvaVT3soXUhcCaNH6_B2mLY_MzICr-c63NJaW4eQ$" target="_blank">https://www.cse.buffalo.edu/~knepley/</a><o:p></o:p></span></p>
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