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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">This makes sense to me. I thought the preallocation only applies to MatCreateMPIAIJwithArrays(…) and other more complicate functions.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">The matrix coming out from ScaLAPACK will be repopulated into a sparse matrix in a much large scale. Do I need to install elemental package in PETSc in order
to use MATELEMENTAL? <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Thanks, Jed.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Jinquan<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> petsc-users-bounces@mcs.anl.gov [mailto:petsc-users-bounces@mcs.anl.gov]
<b>On Behalf Of </b>Jed Brown<br>
<b>Sent:</b> Wednesday, August 08, 2012 11:54 AM<br>
<b>To:</b> PETSc users list<br>
<b>Subject:</b> Re: [petsc-users] Customizeing MatSetValuesBlocked(...)<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Wed, Aug 8, 2012 at 12:47 PM, Jinquan Zhong <<a href="mailto:jzhong@scsolutions.com" target="_blank">jzhong@scsolutions.com</a>> wrote:<o:p></o:p></p>
<p class="MsoNormal">Are you referring to preallocating memory for the size of A before MatSetValues(A, ...)? I didn't do that.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">This is very important.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><a href="http://www.mcs.anl.gov/petsc/documentation/faq.html#efficient-assembly">http://www.mcs.anl.gov/petsc/documentation/faq.html#efficient-assembly</a><o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">With petsc-dev, it is best to use MATELEMENTAL for dense matrices.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">What are you trying to do with this dense martix?<o:p></o:p></p>
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