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Hi Alexandre,</div>
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Sorry about the delay in response to this question. This happens to be a question that we have not encountered before, so we needed to work out how to actually achieve this.</div>
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I am not sure whether this would work, since I don't have an example to test with. I believe that by setting the result in your PRICERREDCOST callback to SCIP_DIDNOTRUN, you will terminate pricing and then continue with the rest of the node processing. The
separation round will begin after you terminate the pricing round.</div>
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There are two things to note here. The first is that if you add a cut, then the node processing will enter back into pricing. So you may want to keep returning the result of SCIP_DIDNOTRUN from your pricer while you want to keep generating cuts. The second
is that if you don't add a cut during the separation round, then you will not enter back into the pricing round. So you must ensure that you have completely finished pricing before the final separation round.</div>
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Since this is untested, please let us know if it works for your setting. If not, then we can think of a different approach.</div>
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Cheers,</div>
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Steve<br>
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<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> Scip <scip-bounces@zib.de> on behalf of Alexandre Dupont-Bouillard <dupont-bouillard@lipn.univ-paris13.fr><br>
<b>Sent:</b> 25 October 2021 09:54<br>
<b>To:</b> scip@zib.de <scip@zib.de><br>
<b>Subject:</b> [SCIP] How to freely tune between pricing and cutting ?</font>
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<br>
<br>
Hi<br>
<br>
We try to build a BCP method where cuts are added through a separator.<br>
We would like to have a free hand on the alternation between pricing and<br>
cutting phases.<br>
<br>
We haven't found how to add parameters to choose for instance to begin<br>
by a cutting phase<br>
or to stop pricing before convergence to add some inequalities and come<br>
back to pricing<br>
and so on...<br>
<br>
The best would be to be able to switch from cutting to pricing (and from<br>
pricing to cutting) using a test done by an algorithm.<br>
<br>
Does someone know how to perform such alternation?<br>
<br>
Thanks<br>
Pierre and Alexandre<br>
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