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Thanks for the clarification. any recommendations to get around this?</div>
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I am solving a set of linear systems of A_i x_i = B_i with matrix-based GMRES. The entries of A_i and B_i are complex numbers. It is pre-conditioned with ASM and the preconditioning matrix is A_i itself. I would like to show the Ritz value to understand the
convergence behaviour for each A_i x_i = B_i. <br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Mark Adams <mfadams@lbl.gov><br>
<b>Sent:</b> 14 July 2022 14:16<br>
<b>To:</b> feng wang <snailsoar@hotmail.com><br>
<b>Cc:</b> petsc-users@mcs.anl.gov <petsc-users@mcs.anl.gov><br>
<b>Subject:</b> Re: [petsc-users] KSPComputeRitz, GMRES, matrix with complex number</font>
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<div dir="ltr">No. I missed that note.
<div>Complex has not been implemented.</div>
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<div dir="ltr" class="x_gmail_attr">On Thu, Jul 14, 2022 at 9:54 AM feng wang <<a href="mailto:snailsoar@hotmail.com">snailsoar@hotmail.com</a>> wrote:<br>
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Hi Mark,</div>
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Thanks for your reply! <br>
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Maybe I have a misunderstanding of the documentation of KSPComputeRitz (<a href="https://petsc.org/main/docs/manualpages/KSP/KSPComputeRitz/" id="x_gmail-m_6877891815980076493LPlnk308872" target="_blank">https://petsc.org/main/docs/manualpages/KSP/KSPComputeRitz/</a>).
It says "-this is currently not implemented when PETSc is built with complex numbers".
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But if it works, I will give it a try.</div>
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Thanks,</div>
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Feng<br>
<pre><span><br></span></pre>
<pre><span><a href="https://petsc.org/main/docs/manualpages/KSP/KSPComputeRitz/" target="_blank"></a></span></pre>
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<div id="x_gmail-m_6877891815980076493divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> Mark Adams <<a href="mailto:mfadams@lbl.gov" target="_blank">mfadams@lbl.gov</a>><br>
<b>Sent:</b> 14 July 2022 12:23<br>
<b>To:</b> feng wang <<a href="mailto:snailsoar@hotmail.com" target="_blank">snailsoar@hotmail.com</a>><br>
<b>Cc:</b> <a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a> <<a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a>><br>
<b>Subject:</b> Re: [petsc-users] KSPComputeRitz, GMRES, matrix with complex number</font>
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<div dir="ltr">Why do you say it only works with Real? You need to configure PETSc to use complex numbers and it should work.
<div>This is an advanced method and it does not have any tests, which basically says it is very experimental.</div>
<div>Don't expect it to be very robust.</div>
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<div>Mark</div>
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<div dir="ltr">On Thu, Jul 14, 2022 at 7:19 AM feng wang <<a href="mailto:snailsoar@hotmail.com" target="_blank">snailsoar@hotmail.com</a>> wrote:<br>
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Dear All,</div>
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I am using GMRES with complex numbers and would like to compute the Ritz values.<span> I am looking at
<a href="https://petsc.org/main/docs/manualpages/KSP/KSPComputeRitz/" target="_blank">
KSPComputeRitz</a> and it seems to me that it only works with Petsc compiled with real numbers. Is there an easy alternative way to compute Ritz values for matrices with complex numbers?</span></div>
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Thanks,</div>
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Feng<br>
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