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<div class="moz-cite-prefix">On 17.08.2012 16:03, Jed Brown wrote:<br>
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<div>Fine, sounds like you are doing divergence cleaning for an
incompatible spatial discretization. Since the change lies
within the null space of the intended continuous operator, you
should be okay. But note that this procedure is fragile and
will have different effect with different Krylov methods and
preconditioning sides.</div>
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Right. <br>
Could you please explain what do you mean by fragile? <br>
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Looks a bit tricky. The number of fgmres iterations then
defines number of the cycles correction will be applied,
doesn't it?</div>
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<div>Yes.</div>
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If I do this command line only setup:<br>
-pc_type composite -pc_composite_type multiplicative
-pc_composite_pcs ksp,shell<br>
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How does petsc know what ShellPCApply routine to take? I guess I
have to specify this in the code anyway?<br>
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<pre class="moz-signature" cols="72">--
Regards,
Alexander</pre>
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