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<p>Dear Kody,</p>
<p><br>
</p>
<p>Just to clarify one thing in case this induced some confusion.</p>
<p>Constraint handlers are defined to add new constraints to the model, while separators would be the suitable mechanism for strengthening the LP relaxation (separators define the algorithms that produce cuts).</p>
<p><br>
</p>
<p>If a constraint handler is still what you think is suitable for your use case, did you implement all corresponding methods?</p>
<p><br>
</p>
<p>Best,<br>
Mathieu<br>
</p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Scip <scip-bounces@zib.de> on behalf of Kody Kazda <17kk18@queensu.ca><br>
<b>Sent:</b> Sunday, November 17, 2024 4:37:27 PM<br>
<b>To:</b> scip@zib.de<br>
<b>Subject:</b> [SCIP] Pyscipopt conshdlr enforcement</font>
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<p class="MsoNormal">Hi all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am looking to implement a constraint handler in pyscipopt to add strengthening cuts to tighten the LP relaxation before branching.<o:p></o:p></p>
<p class="MsoNormal">I have successfully implemented this on other models, but for some unknown reason on the model I am working with now I can’t get pyscipopt to enforce my constraint handler before branching.<o:p></o:p></p>
<p class="MsoNormal">SCIP will get to over 25,000 nodes and still not run my constraint handler.<o:p></o:p></p>
<p class="MsoNormal">I have tried all sorts of different enforcement priorities, going as high as 1E8, so that does not seem to be the issue.<o:p></o:p></p>
<p class="MsoNormal">Does anyone have any thoughts on what might be causing this issue?
<o:p></o:p></p>
<p class="MsoNormal">Is there some algorithmic property that I am not considering that may cause SCIP to not enforce a high priority constraint handler prior to branching?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you!<o:p></o:p></p>
<p class="MsoNormal">Kody<o:p></o:p></p>
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