heur_pscostdiving.c
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22 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
47 #define DIVESET_DIVETYPES SCIP_DIVETYPE_INTEGRALITY /**< bit mask that represents all supported dive types */
48 #define DIVESET_ISPUBLIC TRUE /**< is this dive set publicly available (ie., can be used by other primal heuristics?) */
57 #define DEFAULT_MAXLPITERQUOT 0.05 /**< maximal fraction of diving LP iterations compared to node LP iterations */
59 #define DEFAULT_MAXDIVEUBQUOT 0.8 /**< maximal quotient (curlowerbound - lowerbound)/(cutoffbound - lowerbound)
61 #define DEFAULT_MAXDIVEAVGQUOT 0.0 /**< maximal quotient (curlowerbound - lowerbound)/(avglowerbound - lowerbound)
63 #define DEFAULT_MAXDIVEUBQUOTNOSOL 0.1 /**< maximal UBQUOT when no solution was found yet (0.0: no limit) */
64 #define DEFAULT_MAXDIVEAVGQUOTNOSOL 0.0 /**< maximal AVGQUOT when no solution was found yet (0.0: no limit) */
65 #define DEFAULT_BACKTRACK TRUE /**< use one level of backtracking if infeasibility is encountered? */
66 #define DEFAULT_LPRESOLVEDOMCHGQUOT 0.15 /**< percentage of immediate domain changes during probing to trigger LP resolve */
68 #define DEFAULT_ONLYLPBRANCHCANDS TRUE /**< should only LP branching candidates be considered instead of the slower but
176 /* terminate if there are no integer variables (note that, e.g., SOS1 variables may be present) */
180 SCIP_CALL( SCIPperformGenericDivingAlgorithm(scip, diveset, heurdata->sol, heur, result, nodeinfeasible, -1L, SCIP_DIVECONTEXT_SINGLE) );
207 /* determine the candidate direction. if the variable may be trivially rounded in one direction, take the other direction;
208 * otherwise, consider first the direction from the root solution, second the candidate fractionality, and
211 * to avoid performance variability caused by numerics we use random numbers to decide whether we want to roundup or
218 || (SCIPisEQ(scip, candsol, SCIPvarGetRootSol(cand) - 0.4) && SCIPrandomGetInt(SCIPdivesetGetRandnumgen(diveset), 0, 1) == 0) )
221 || (SCIPisEQ(scip, candsol, SCIPvarGetRootSol(cand) + 0.4) && SCIPrandomGetInt(SCIPdivesetGetRandnumgen(diveset), 0, 1) == 0) )
224 || (SCIPisEQ(scip, candsfrac, 0.3) && SCIPrandomGetInt(SCIPdivesetGetRandnumgen(diveset), 0, 1) == 0) )
227 || (SCIPisEQ(scip, candsfrac, 0.7) && SCIPrandomGetInt(SCIPdivesetGetRandnumgen(diveset), 0, 1) == 0) )
261 {
281 /* create a diveset (this will automatically install some additional parameters for the heuristic)*/
282 SCIP_CALL( SCIPcreateDiveset(scip, NULL, heur, HEUR_NAME, DEFAULT_MINRELDEPTH, DEFAULT_MAXRELDEPTH, DEFAULT_MAXLPITERQUOT,
283 DEFAULT_MAXDIVEUBQUOT, DEFAULT_MAXDIVEAVGQUOT, DEFAULT_MAXDIVEUBQUOTNOSOL, DEFAULT_MAXDIVEAVGQUOTNOSOL, DEFAULT_LPRESOLVEDOMCHGQUOT,
284 DEFAULT_LPSOLVEFREQ, DEFAULT_MAXLPITEROFS, DEFAULT_RANDSEED, DEFAULT_BACKTRACK, DEFAULT_ONLYLPBRANCHCANDS,
285 DIVESET_ISPUBLIC, DIVESET_DIVETYPES, divesetGetScorePscostdiving, divesetAvailablePscostdiving) );
SCIP_Bool SCIPisEQ(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
Definition: scip_numerics.c:438
Definition: type_result.h:33
Definition: struct_scip.h:59
public methods for memory management
Definition: type_heur.h:60
SCIP_RANDNUMGEN * SCIPdivesetGetRandnumgen(SCIP_DIVESET *diveset)
Definition: heur.c:700
SCIP_RETCODE SCIPperformGenericDivingAlgorithm(SCIP *scip, SCIP_DIVESET *diveset, SCIP_SOL *worksol, SCIP_HEUR *heur, SCIP_RESULT *result, SCIP_Bool nodeinfeasible, SCIP_Longint iterlim, SCIP_DIVECONTEXT divecontext)
Definition: heuristics.c:209
methods commonly used by primal heuristics
public methods for problem variables
LP diving heuristic that chooses fixings w.r.t. the pseudo cost values.
public methods for SCIP variables
SCIP_RETCODE SCIPsetHeurInit(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURINIT((*heurinit)))
Definition: scip_heur.c:185
public methods for numerical tolerances
SCIP_RETCODE SCIPcreateSol(SCIP *scip, SCIP_SOL **sol, SCIP_HEUR *heur)
Definition: scip_sol.c:320
Definition: struct_sol.h:64
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:108
static SCIP_DECL_HEURFREE(heurFreePscostdiving)
Definition: heur_pscostdiving.c:106
void SCIPheurSetData(SCIP_HEUR *heur, SCIP_HEURDATA *heurdata)
Definition: heur.c:1350
static SCIP_DECL_HEUREXIT(heurExitPscostdiving)
Definition: heur_pscostdiving.c:146
Definition: type_retcode.h:33
Definition: struct_heur.h:88
public methods for primal heuristic plugins and divesets
public data structures and miscellaneous methods
int SCIPrandomGetInt(SCIP_RANDNUMGEN *randnumgen, int minrandval, int maxrandval)
Definition: misc.c:9945
SCIP_RETCODE SCIPincludeHeurPscostdiving(SCIP *scip)
Definition: heur_pscostdiving.c:261
SCIP_RETCODE SCIPsetHeurExit(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEUREXIT((*heurexit)))
Definition: scip_heur.c:201
Definition: struct_heur.h:58
static SCIP_DECL_DIVESETGETSCORE(divesetGetScorePscostdiving)
Definition: heur_pscostdiving.c:191
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:311
public methods for solutions
SCIP_RETCODE SCIPsetHeurCopy(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURCOPY((*heurcopy)))
Definition: scip_heur.c:153
public methods for message output
SCIP_Real SCIPgetVarPseudocostVal(SCIP *scip, SCIP_VAR *var, SCIP_Real solvaldelta)
Definition: scip_var.c:8747
SCIP_Bool SCIPisLT(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
Definition: scip_numerics.c:451
SCIP_Bool SCIPisGT(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
Definition: scip_numerics.c:477
static SCIP_DECL_HEURINIT(heurInitPscostdiving)
Definition: heur_pscostdiving.c:126
SCIP_RETCODE SCIPsetHeurFree(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURFREE((*heurfree)))
Definition: scip_heur.c:169
static SCIP_DECL_HEUREXEC(heurExecPscostdiving)
Definition: heur_pscostdiving.c:165
public methods for primal heuristics
Definition: objbenders.h:33
public methods for global and local (sub)problems