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<div class="moz-cite-prefix">On 17.08.2012 15:30, Jed Brown wrote:<br>
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cite="mid:CAM9tzSm6_v9jX5PJMPjrDd0AF3GvLJm=6b5DL-1ZvO5YdiB=0A@mail.gmail.com"
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<div class="gmail_quote"><br>
<div>Sorry, I misinterpreted what you want.
PC_COMPOSITE_MULTIPLICATIVE re-evaluates the residual after
applying the first stage of the preconditioner. Do you
_really_ want to just apply one preconditioner after the next?
You can use PC_COMPOSITE_SPECIAL, but read this man page and
understand why your preconditioner has that form. <a
moz-do-not-send="true"
href="http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/PC/PCCompositeType.html">http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/PC/PCCompositeType.html</a></div>
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<br>
Jed,<br>
<br>
I've seen this, but I'm not sure is it fits me.<br>
<br>
What I would like to do is very simple: every N iterations I want to
take current solution vector <b>x</b>_i from KSP and calculate:<br>
<b>x</b>_i = <b>x</b>_i + <b>c</b>,<br>
where <b>c</b> is a correction vector. I want to be able to apply
other preconditioners in a usual way. <br>
<br>
Is it possible?<br>
<pre class="moz-signature" cols="72">--
Regards,
Alexander</pre>
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