heur_pscostdiving.c
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31/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
56#define DIVESET_DIVETYPES SCIP_DIVETYPE_INTEGRALITY /**< bit mask that represents all supported dive types */
57#define DIVESET_ISPUBLIC TRUE /**< is this dive set publicly available (ie., can be used by other primal heuristics?) */
66#define DEFAULT_MAXLPITERQUOT 0.05 /**< maximal fraction of diving LP iterations compared to node LP iterations */
68#define DEFAULT_MAXDIVEUBQUOT 0.8 /**< maximal quotient (curlowerbound - lowerbound)/(cutoffbound - lowerbound)
70#define DEFAULT_MAXDIVEAVGQUOT 0.0 /**< maximal quotient (curlowerbound - lowerbound)/(avglowerbound - lowerbound)
72#define DEFAULT_MAXDIVEUBQUOTNOSOL 0.1 /**< maximal UBQUOT when no solution was found yet (0.0: no limit) */
73#define DEFAULT_MAXDIVEAVGQUOTNOSOL 0.0 /**< maximal AVGQUOT when no solution was found yet (0.0: no limit) */
74#define DEFAULT_BACKTRACK TRUE /**< use one level of backtracking if infeasibility is encountered? */
75#define DEFAULT_LPRESOLVEDOMCHGQUOT 0.15 /**< percentage of immediate domain changes during probing to trigger LP resolve */
77#define DEFAULT_ONLYLPBRANCHCANDS TRUE /**< should only LP branching candidates be considered instead of the slower but
185 /* terminate if there are no integer variables (note that, e.g., SOS1 variables may be present) */
189 SCIP_CALL( SCIPperformGenericDivingAlgorithm(scip, diveset, heurdata->sol, heur, result, nodeinfeasible, -1L, -1, -1.0, SCIP_DIVECONTEXT_SINGLE) );
216 /* determine the candidate direction. if the variable may be trivially rounded in one direction, take the other direction;
217 * otherwise, consider first the direction from the root solution, second the candidate fractionality, and
220 * to avoid performance variability caused by numerics we use random numbers to decide whether we want to roundup or
227 || (SCIPisEQ(scip, candsol, SCIPvarGetRootSol(cand) - 0.4) && SCIPrandomGetInt(SCIPdivesetGetRandnumgen(diveset), 0, 1) == 0) )
230 || (SCIPisEQ(scip, candsol, SCIPvarGetRootSol(cand) + 0.4) && SCIPrandomGetInt(SCIPdivesetGetRandnumgen(diveset), 0, 1) == 0) )
233 || (SCIPisEQ(scip, candsfrac, 0.3) && SCIPrandomGetInt(SCIPdivesetGetRandnumgen(diveset), 0, 1) == 0) )
236 || (SCIPisEQ(scip, candsfrac, 0.7) && SCIPrandomGetInt(SCIPdivesetGetRandnumgen(diveset), 0, 1) == 0) )
290 /* create a diveset (this will automatically install some additional parameters for the heuristic)*/
291 SCIP_CALL( SCIPcreateDiveset(scip, NULL, heur, HEUR_NAME, DEFAULT_MINRELDEPTH, DEFAULT_MAXRELDEPTH, DEFAULT_MAXLPITERQUOT,
292 DEFAULT_MAXDIVEUBQUOT, DEFAULT_MAXDIVEAVGQUOT, DEFAULT_MAXDIVEUBQUOTNOSOL, DEFAULT_MAXDIVEAVGQUOTNOSOL, DEFAULT_LPRESOLVEDOMCHGQUOT,
293 DEFAULT_LPSOLVEFREQ, DEFAULT_MAXLPITEROFS, DEFAULT_RANDSEED, DEFAULT_BACKTRACK, DEFAULT_ONLYLPBRANCHCANDS,
294 DIVESET_ISPUBLIC, DIVESET_DIVETYPES, divesetGetScorePscostdiving, divesetAvailablePscostdiving) );
SCIP_RETCODE SCIPincludeHeurPscostdiving(SCIP *scip)
Definition: heur_pscostdiving.c:267
SCIP_RETCODE SCIPcreateDiveset(SCIP *scip, SCIP_DIVESET **diveset, SCIP_HEUR *heur, const char *name, SCIP_Real minreldepth, SCIP_Real maxreldepth, SCIP_Real maxlpiterquot, SCIP_Real maxdiveubquot, SCIP_Real maxdiveavgquot, SCIP_Real maxdiveubquotnosol, SCIP_Real maxdiveavgquotnosol, SCIP_Real lpresolvedomchgquot, int lpsolvefreq, int maxlpiterofs, unsigned int initialseed, SCIP_Bool backtrack, SCIP_Bool onlylpbranchcands, SCIP_Bool ispublic, SCIP_Bool specificsos1score, SCIP_DECL_DIVESETGETSCORE((*divesetgetscore)), SCIP_DECL_DIVESETAVAILABLE((*divesetavailable)))
Definition: scip_heur.c:318
SCIP_RANDNUMGEN * SCIPdivesetGetRandnumgen(SCIP_DIVESET *diveset)
Definition: heur.c:720
SCIP_RETCODE SCIPsetHeurCopy(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURCOPY((*heurcopy)))
Definition: scip_heur.c:162
SCIP_RETCODE SCIPincludeHeurBasic(SCIP *scip, SCIP_HEUR **heur, const char *name, const char *desc, char dispchar, int priority, int freq, int freqofs, int maxdepth, SCIP_HEURTIMING timingmask, SCIP_Bool usessubscip, SCIP_DECL_HEUREXEC((*heurexec)), SCIP_HEURDATA *heurdata)
Definition: scip_heur.c:117
SCIP_RETCODE SCIPsetHeurFree(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURFREE((*heurfree)))
Definition: scip_heur.c:178
SCIP_RETCODE SCIPsetHeurExit(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEUREXIT((*heurexit)))
Definition: scip_heur.c:210
SCIP_RETCODE SCIPsetHeurInit(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURINIT((*heurinit)))
Definition: scip_heur.c:194
void SCIPheurSetData(SCIP_HEUR *heur, SCIP_HEURDATA *heurdata)
Definition: heur.c:1374
SCIP_RETCODE SCIPcreateSol(SCIP *scip, SCIP_SOL **sol, SCIP_HEUR *heur)
Definition: scip_sol.c:184
SCIP_RETCODE SCIPperformGenericDivingAlgorithm(SCIP *scip, SCIP_DIVESET *diveset, SCIP_SOL *worksol, SCIP_HEUR *heur, SCIP_RESULT *result, SCIP_Bool nodeinfeasible, SCIP_Longint iterlim, int nodelimit, SCIP_Real lpresolvedomchgquot, SCIP_DIVECONTEXT divecontext)
Definition: heuristics.c:220
SCIP_Bool SCIPisGT(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
Definition: scip_numerics.c:484
SCIP_Bool SCIPisEQ(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
Definition: scip_numerics.c:445
SCIP_Bool SCIPisLT(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
Definition: scip_numerics.c:458
SCIP_Real SCIPgetVarPseudocostVal(SCIP *scip, SCIP_VAR *var, SCIP_Real solvaldelta)
Definition: scip_var.c:8814
int SCIPrandomGetInt(SCIP_RANDNUMGEN *randnumgen, int minrandval, int maxrandval)
Definition: misc.c:10108
static SCIP_DECL_DIVESETGETSCORE(divesetGetScorePscostdiving)
Definition: heur_pscostdiving.c:197
static SCIP_DECL_HEURINIT(heurInitPscostdiving)
Definition: heur_pscostdiving.c:132
static SCIP_DECL_HEUREXIT(heurExitPscostdiving)
Definition: heur_pscostdiving.c:152
static SCIP_DECL_HEURFREE(heurFreePscostdiving)
Definition: heur_pscostdiving.c:112
static SCIP_DECL_HEUREXEC(heurExecPscostdiving)
Definition: heur_pscostdiving.c:171
LP diving heuristic that chooses fixings w.r.t. the pseudo cost values.
methods commonly used by primal heuristics
Definition: objbenders.h:44
public methods for primal heuristics
public methods for message output
public data structures and miscellaneous methods
public methods for problem variables
public methods for primal heuristic plugins and divesets
public methods for memory management
public methods for numerical tolerances
public methods for global and local (sub)problems
public methods for solutions
public methods for SCIP variables
Definition: struct_heur.h:68
Definition: struct_heur.h:98
Definition: struct_sol.h:74
Definition: struct_scip.h:70