[SCIP] Separating all Cliques from the Clique table

[Linß, Andreas]

Dear scip community,

I have a huge amount of possible clique cuts, which i have as set packing constraints in the model.

Now I have exactly these inequalities in my presolver as cliques to the clique graph (SCIPaddClique).

When separating using the Set-Packing Constraint handler, all cliques are found and now constraints is violated. If I comment out the addition of the Set-Packing Constraints, some cliques are separated. However, some of the cliques I add to the clique graph are still severely violated with a sum value of 1.5.  The corresponding cut also has an efficiousness of 0.133631.

Is it possible to tell the clique separator to separate all possible clique-cuts, that are violated by the current solution?
My actual settings in scip-optsuite-7.0.1 are :

presolving/../maxrounds=0
heuristics/../freq = -1
propagating/../maxprerounds = 0
propagating/../freq = -1
separating/../freq = -1
separating/clique/priority = 10000000
separating/clique/freq = 1
separate/minorthoroot = 0.1
separating/clique/maxsepacuts = 1000000
separate/minefficacyroot = 0.0001
separating/maxstallrounds = -1
separate/poolfreq = 1
separating/clique/maxzeroextensions = -1

As an extension of my question:
is it perhaps more efficient to have the clique cuts in the model as Set-Packing Constraints (initial = false, separate = true), even if there are a lot of them, and only separate more specific cliques with the Clique generator?


Many thanks for the support!

Kind regards
Andreas Linß


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