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<p class="MsoNormal"><span style="font-size:11.0pt">Thanks Barry,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">I saw that function, but wasn’t sure how to apply it since the documentation says that S and T are dense matrices, but in my case all matrices involved are sparse. Is there a way to work around the dense
requirement?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Best,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Tyler<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><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">Barry Smith <bsmith@petsc.dev><br>
<b>Date: </b>Monday, January 30, 2023 at 11:12 AM<br>
<b>To: </b>Guglielmo, Tyler Hardy <guglielmo2@llnl.gov><br>
<b>Cc: </b>petsc-users@mcs.anl.gov <petsc-users@mcs.anl.gov><br>
<b>Subject: </b>Re: [petsc-users] Kronecker Product<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"> Do you need the explicit sparse representation of the Kronecker product? Or do you want to apply it as an operator or solve systems with it? If the latter you can use <a href="https://urldefense.us/v3/__https:/petsc.org/release/docs/manualpages/Mat/MatCreateKAIJ/*matcreatekaij__;Iw!!G2kpM7uM-TzIFchu!lSQ9WFlYi6PMdfs3WAfEq4ydgCLZtfDgyFy9PjdLNTisCsHtwmVuukcpIv1J0i1EtiQ$">https://petsc.org/release/docs/manualpages/Mat/MatCreateKAIJ/#matcreatekaij</a><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"> Barry<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">On Jan 30, 2023, at 12:53 PM, Guglielmo, Tyler Hardy via petsc-users <petsc-users@mcs.anl.gov> wrote:<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Hi all,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"> <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">I am wondering if there is any functionality for taking Kronecker products of large sparse matrices that are parallel? MatSeqAIJKron is as close as I have found, but it seems like this does not work for parallel
matrices. Any ideas here? <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"> <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">An option could be to make A and B sequential, compute the Kronecker product, C, then scatter C into a parallel matrix? This seems like a horribly inefficient procedure. I’m still fairly new to petsc, so
thanks for patience :)!<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"> <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Best,<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Tyler<span class="apple-converted-space"> </span><o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"> <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">+++++++++++++++++++++++++++++<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Tyler Guglielmo<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Postdoctoral Researcher<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Lawrence Livermore National Lab<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Office: 925-423-6186<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">Cell: 210-480-8000<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">+++++++++++++++++++++++++++++<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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