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Hi,</div>
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I wrote:</div>
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"Is there a way to activate relaxations like scip/examples/Relaxator/src/relax_nlp.c during a concurrent solve, or when using parascip? It works fine for a serial optimization, but seems to be ignored otherwise."</div>
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I found one way to do it is to make the call on the last line (and pulling the Relax NLP into the main code) in the file concsolver_scip.c. Something similar would be needed in UG.
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<span> /* create the concurrent solver's SCIP instance and set up the problem */<br>
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<div> SCIP_CALL( SCIPcreate(&data->solverscip) );<br>
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<div> SCIP_CALL( SCIPhashmapCreate(&varmapfw, SCIPblkmem(data->solverscip), data->nvars) );<br>
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<div> SCIP_CALL( SCIPcopy(scip, data->solverscip, varmapfw, NULL, SCIPconcsolverGetName(concsolver), TRUE, FALSE, FALSE, &valid) );<br>
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<div> assert(valid);<br>
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<div> SCIPincludeRelaxNlp(data->solverscip);</div>
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<div>A general way to do it is to make that call in a copy routine in that relax_nlp.c. However, that has the problem that sub-SCIPs (e.g. heuristics) will invoke the relaxation, which can be very expensive.</div>
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<div>Marcus<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Marcus Daniels<br>
<b>Sent:</b> Saturday, December 28, 2019 6:31 PM<br>
<b>To:</b> scip@zib.de <scip@zib.de><br>
<b>Subject:</b> Relaxation handler and concurrent solver</font>
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Hello,</div>
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Is there a way to activate relaxations like scip/examples/Relaxator/src/relax_nlp.c during a concurrent solve, or when using parascip? It works fine for a serial optimization, but seems to be ignored otherwise.<br>
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Thanks,</div>
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Marcus Daniels<br>
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