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<div class="moz-cite-prefix">On 12/28/2014 05:54 PM, Alp Kalpalp
wrote:<br>
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<div>Hi, <br>
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Thank you Mark. <br>
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Let me clarify my questions;<br>
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1-)How to implement or activate a Reorthogonalization
procedure for KSPCG..<br>
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<div>As you know, search directions can be found more rapidly
(with less numer of iterations) by using previous successive
directions<br>
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Without answering the PETSc related questions, interesting
discussion, <br>
<br>
indeed, but at the cost of purging the previous directions(which
means explicit orthogonalizations with respect to these vectors
also), so I am not sure if you can gain something with this, cost
wise...<br>
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2-) How to implement or activate a projection space over CG. A
sample projection can be;<br>
P = I - G*((G'*G)\G'). <br>
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I need to insert project,scale,precondition,re-scae,re-project
steps during each KSPCG iteration. How can I utilize this?<br>
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Just a side note, I had previous experience on this that these kinds
of practice increase the cost more...<br>
BR,<br>
Umut<br>
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