<!doctype html>
<html>
<head>
<meta charset="UTF-8">
</head>
<body>
<div>
Thank you for butting in. I did not know about this format. I reply to the mailing list because others might find it useful too.
</div>
<blockquote type="cite">
<div>
João Dionísio <joao.goncalves.dionisio@gmail.com> hat am 13.06.2025 10:02 CEST geschrieben:
</div>
<div>
</div>
<div>
</div>
<div dir="ltr">
Dear Johann-Tobias,
<div>
</div>
<div>
Just butting in to say that if what you want is something similar to the <a href="https://gcg.or.rwth-aachen.de/doc-3.5.0/own-dec-file.html">dec file format</a>, which informs SCIP/GCG about available decompositions, then such a format does not exist for symmetries. As far as I'm aware, that is the case in SCIP and everywhere else. I'm not a symmetry person, so I'm not sure how difficult it would be to implement it, or if it would be useful.
</div>
<div>
</div>
<div>
Hopefully, this answers the original <a href="http://OR.SE">OR.SE</a> question.
</div>
<div>
</div>
<div>
Best,
</div>
<div>
João Dionísio
</div>
</div>
<br>
<div class="gmail_quote gmail_quote_container">
<div class="gmail_attr" dir="ltr">
On Thu, Jun 12, 2025 at 11:12 AM Johann-Tobias Schäg <<a href="mailto:johann-tobias@sch%C3%A4g.de">johann-tobias@schäg.de</a>> wrote:
</div>
<blockquote>
<u></u>
<div>
<div>
I am aware that there are mutliple ways to handle symmetries in SCIP
</div>
<div>
</div>
<div>
<a href="https://www.scipopt.org/doc/html/cons__orbisack_8h.php" target="_blank" rel="noopener">https://www.scipopt.org/doc/html/cons__orbisack_8h.php</a>
</div>
<div>
<a href="https://www.scipopt.org/doc/html/cons__orbitope_8h.php" target="_blank" rel="noopener">https://www.scipopt.org/doc/html/cons__orbitope_8h.php</a>
</div>
<div>
<a href="https://www.scipopt.org/doc/html/cons__symresack_8h.php" target="_blank" rel="noopener">https://www.scipopt.org/doc/html/cons__symresack_8h.php</a>
</div>
<div>
</div>
<div>
All those are for binary variables.
</div>
<div>
</div>
<div>
I occasionally encounter 0-1 ILP which have symmetries so large that SCIP fails to (fully) detect them. I asked on the OR stack exchange whether there is a standardized format for symmetry groups: <a href="https://or.stackexchange.com/questions/13187/are-there-existing-formats-to-express-symmetries-between-variables-in-milp?noredirect=1#comment28418_13187" target="_blank" rel="noopener">https://or.stackexchange.com/questions/13187/are-there-existing-formats-to-express-symmetries-between-variables-in-milp?noredirect=1#comment28418_13187</a> and was pointed towards SCIP being potentially interesting for that.
</div>
<div>
</div>
<div>
Is there some examples which use those constraints handlers?
</div>
<div>
The documentation i linked above is to dense for me to make sense of.
</div>
<div>
</div>
<div>
Sincerely,
<br>Johann-Tobias Schäg
</div>
<div>
</div>
<div>
</div>
</div> _______________________________________________
<br>Scip mailing list
<br><a href="mailto:Scip@zib.de" target="_blank" rel="noopener">Scip@zib.de</a>
<br><a href="https://listserv.zib.de/mailman/listinfo/scip" target="_blank" rel="noopener">https://listserv.zib.de/mailman/listinfo/scip</a>
</blockquote>
</div>
</blockquote>
</body>
</html>