[Scip] cutting plane questions

[Felix Breuer]

Hello everyone!

I am trying to solve a hard mixed-integer program to optimality. However,
branch and bound seems to be largely ineffective at finding an optimal
solution, simply because the search space is way too large. (There are 512
binary variables in my program, and I know for theoretical reasons that all
2^512 ways of fixing these variables lead to a feasible solution.) I'd like
to experiment with using cutting planes more aggressively to solve the
problem, and I have a couple of questions:

0) The "cuts" given by SCIP on the command line when solving the problem -
do these number give the number of cuts currently in the system, or do they
give the total number of cuts that have been added in the entire run?

1) I tried adjusting the many parameters the SCIP offers for controlling
separators. However, I have been unable to make SCIP use more than about
150 cuts. How can make SCIP use even more cutting planes?

2) In particular, is there a way to configure SCIP not to use
branch-and-bound at all but only cutting planes to solve the problem? I
know that conventional wisdom says this is hopelessly inefficient. But I'd
like to investigate how this approach fares on my problems.

Thank you!

Felix



-- 
http://www.felixbreuer.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://listserv.zib.de/pipermail/scip/attachments/20130728/620e54b9/attachment.html