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<p style="margin-top:0;margin-bottom:0">Thanks Jose!</p>
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<p style="margin-top:0;margin-bottom:0">all the best</p>
<p style="margin-top:0;margin-bottom:0">--cjc</p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Jose E. Roman <jroman@dsic.upv.es><br>
<b>Sent:</b> 16 January 2019 09:55:08<br>
<b>To:</b> Cotter, Colin J<br>
<b>Cc:</b> petsc-users@mcs.anl.gov<br>
<b>Subject:</b> Re: [petsc-users] SLEPc: Setting options for mass matrix KSP in generalised eigenvalue problem</font>
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<div class="PlainText">This case is treated in the same way as the (shift-and-invert) spectral transformation. There are nested objects EPS > ST > KSP > PC. By default ST=SHIFT, which is what you need. So you just have to get access to the KSP/PC objects to
set options.<br>
<br>
Basically you can use ex9.py in slepc4py but use F.setType(F.Type.SHIFT) instead of F.setType(F.Type.PRECOND).<br>
<br>
Jose<br>
<br>
<br>
> El 16 ene 2019, a las 10:32, Cotter, Colin J via petsc-users <petsc-users@mcs.anl.gov> escribió:<br>
> <br>
> Dear PETSc mailing list,<br>
> A SLEPc question, sorry if this is obvious and I missed something.<br>
> <br>
> How do I set the KSP for the mass matrix M in the generalised eigenvalue problem<br>
> (I'm looking for the eigenvalue with largest magnitude)<br>
> <br>
> Ax = lambda*Mx<br>
> <br>
> ?<br>
> <br>
> I can only find how to set the KSP for a spectral transform. <br>
> <br>
> (I'm actually using slepc4py)<br>
> <br>
> all the best<br>
> -_Colin<br>
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