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<p class="MsoNormal">If I am correct, to do this, it will double the peak memory usage.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is there any way no to double the peak memory usage?<o:p></o:p></p>
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<span style="font-size:10.0pt;color:black">Schlumberger-Private</span><o:p></o:p></p>
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<p class="MsoNormal"><b>From:</b> Barry Smith <bsmith@petsc.dev> <br>
<b>Sent:</b> Monday, August 31, 2020 1:56 PM<br>
<b>To:</b> Kun Jiao <KJiao@slb.com><br>
<b>Cc:</b> petsc-users <petsc-users@mcs.anl.gov><br>
<b>Subject:</b> [Ext] Re: [petsc-users] change matrix<o:p></o:p></p>
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<p class="MsoNormal"> Kun,<o:p></o:p></p>
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<p class="MsoNormal"> This is not possible, PETSc matrices have a static size (resizing in parallel is tricky so we don't support it). <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"> If it is more efficient to reuse the matrix entries than recompute them you can create a larger matrix and then loop over the old matrix calling MatGetRow() and then call MatSetValues() to copy that row into the new matrix.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"> Barry<o:p></o:p></p>
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<p class="MsoNormal">On Aug 31, 2020, at 1:51 PM, Kun Jiao via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Hi Petsc Experts,<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Trying to do something like appending some rows (~100 rows) to an already created matrix, but could not find any document about it.<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Could anyone provide some information about it?<o:p></o:p></p>
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<p class="MsoNormal"> <o:p></o:p></p>
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<p class="MsoNormal">Regards,<o:p></o:p></p>
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<p class="MsoNormal">Kun<o:p></o:p></p>
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<p class="MsoNormal"><span style="font-size:13.5pt;font-family:"Helvetica",sans-serif"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt">Schlumberger-Private</span><span style="font-size:13.5pt;font-family:"Helvetica",sans-serif"><o:p></o:p></span></p>
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