[SCIP] cuts before branching begins

[Stefan Vigerske]

Hi,

maybe try
   constraints/quadratic/sepanlpmincont = 2.0
   constraints/quadratic/linearizeheursol = FALSE
but that may not be sufficient.
After the separation loop, if there are no fractional integer variables, 
then cuts may be added for quadratic constraints if possible, as this 
can be preferable over branching. If quadratic constraints are convex, 
then there is no use in branching, too.

You could also add a
   *result = SCIP_DIDNOTFIND;
   return SCIP_OKAY;
at the beginning of cons_quadratic.c:separatePoint(), but weird things 
may happen :).

Stefan

On 1/22/20 2:09 AM, Marcus Daniels wrote:
> Hi Leona, all,
> 
> Ok, the cuts are added by the quadratic constraint.  I found reducing constraints/quadratic/cutmaxrange is a way to minimize them.  Is there a better way?
> 
> Thanks,
> 
> Marcus
> 
> From: Scip <scip-bounces at zib.de> on behalf of Leona Gottwald <gottwald at zib.de>
> Date: Tuesday, January 21, 2020 at 8:41 AM
> To: "scip at zib.de" <scip at zib.de>
> Subject: Re: [SCIP] cuts before branching begins
> 
> 
> Hi Marcus,
> 
> 
> 
> try to display the statistics of SCIP. The source of the cuts could be a separator or a constraint handler. In the statistics you will see how many cuts are added by separators and constraint handlers.
> 
> 
> 
> The statistics can be printed in the command line with "display statistics" and in the callable library with SCIPprintStatistics().
> 
> 
> 
> Best,
> Leona
> 
> 
> On 1/21/20 5:28 PM, Marcus Daniels wrote:
> Hi,
> 
> I have a problem where I see an extensive set of cuts (e.g. 10,000) before branching starts.   I tried disabling separation both at the command line level and programmatically in my sub-problem, but I still see them being added.   I also tried setting separating/maxcutsroot to 0.   What is the source of these cuts and can I disable them?
> 
> Thanks,
> 
> Marcus
> 
> 
> 
> _______________________________________________
> 
> Scip mailing list
> 
> Scip at zib.de<mailto:Scip at zib.de>
> 
> https://listserv.zib.de/mailman/listinfo/scip
> 
> 
> _______________________________________________
> Scip mailing list
> Scip at zib.de
> https://listserv.zib.de/mailman/listinfo/scip
>