Scippy

    SCIP

    Solving Constraint Integer Programs

    Functions
    branch_lookahead.h File Reference
    Public API of SCIP » Plugin API of SCIP » Branching Rules

    Detailed Description

    lookahead LP branching rule

    Author
    Christoph Schubert
    Gerald Gamrath

    The (multi-level) lookahead branching rule applies strong branching to every fractional value of the LP solution at the current node of the branch-and-bound tree, as well as recursivly to every temporary child problem created by this strong branching. The rule selects the candidate with the best proven dual bound.

    The branching rule was motivated by the following technical report:

    Wasu Glankwamdee and Jeff Linderoth
    Lookahead Branching for Mixed Integer Programming
    Technical Report 06T-004, Department of Industrial and Systems Engineering, Lehigh University.

    For a more mathematical description and a comparison between lookahead branching and other branching rules in SCIP, we refer to

    Christoph Schubert
    Multi-Level Lookahead Branching
    Master Thesis, Technische Universität Berlin, 2017

    Definition in file branch_lookahead.h.

    #include "scip/def.h"
    #include "scip/type_retcode.h"
    #include "scip/type_scip.h"

    Go to the source code of this file.

    Functions

    SCIP_RETCODE SCIPincludeBranchruleLookahead (SCIP *scip)
     

    Function Documentation

    ◆ SCIPincludeBranchruleLookahead()

    SCIP_RETCODE SCIPincludeBranchruleLookahead ( SCIP *  scip)

    creates the lookahead branching rule and includes it in SCIP

    Parameters
    scipSCIP data structure

    Definition at line 6209 of file branch_lookahead.c.

    References BRANCHRULE_DESC, BRANCHRULE_MAXBOUNDDIST, BRANCHRULE_MAXDEPTH, BRANCHRULE_NAME, BRANCHRULE_PRIORITY, DEFAULT_ABBREVIATED, DEFAULT_ABBREVPSEUDO, DEFAULT_ADDBINCONSROW, DEFAULT_ADDCLIQUE, DEFAULT_ADDNONVIOCONS, DEFAULT_APPLYCHILDBOUNDS, DEFAULT_DEEPERSCORINGFUNCTION, DEFAULT_ENFORCEMAXDOMREDS, DEFAULT_FILTERBYMAXGAIN, DEFAULT_LEVEL2AVGSCORE, DEFAULT_LEVEL2ZEROSCORE, DEFAULT_MAXNCANDS, DEFAULT_MAXNDEEPERCANDS, DEFAULT_MAXNVIOLATEDBINCONS, DEFAULT_MAXNVIOLATEDCONS, DEFAULT_MAXNVIOLATEDDOMREDS, DEFAULT_MAXPROPROUNDS, DEFAULT_MERGEDOMAINREDUCTIONS, DEFAULT_MINWEIGHT, DEFAULT_ONLYVIOLDOMREDS, DEFAULT_PREFERSIMPLEBOUNDS, DEFAULT_PROPAGATE, DEFAULT_RECURSIONDEPTH, DEFAULT_REEVALAGE, DEFAULT_REEVALAGEFSB, DEFAULT_REUSEBASIS, DEFAULT_SCORINGFUNCTION, DEFAULT_SCORINGSCORINGFUNCTION, DEFAULT_STOREUNVIOLATEDSOL, DEFAULT_UPDATEBRANCHINGRESULTS, DEFAULT_USEBINARYCONSTRAINTS, DEFAULT_USEDOMAINREDUCTION, DEFAULT_USELEVEL2DATA, DEFAULT_WORSEFACTOR, FALSE, NULL, SCIP_CALL, SCIP_LONGINT_MAX, SCIP_OKAY, SCIP_REAL_MAX, SCIPaddBoolParam(), SCIPaddCharParam(), SCIPaddIntParam(), SCIPaddLongintParam(), SCIPaddRealParam(), SCIPallocBlockMemory, SCIPincludeBranchruleBasic(), SCIPsetBranchruleCopy(), SCIPsetBranchruleExecLp(), SCIPsetBranchruleExit(), SCIPsetBranchruleExitsol(), SCIPsetBranchruleFree(), SCIPsetBranchruleInit(), and TRUE.

    Referenced by SCIP_DECL_BRANCHCOPY(), and SCIPincludeDefaultPlugins().