heur_indicator.c
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27 * @brief handle partial solutions for linear problems with indicators and otherwise continuous variables
30 * For linear problems with indicators and otherwise continuous variables, the indicator constraint handler can produce
31 * partial solutions, i.e., values for the indicator variables. This partial solution can be passed to this heuristic,
32 * which then fixes these values and solves an LP. Additionally a local search for a better solution is added.
35 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
61 #define HEUR_DESC "indicator heuristic to create feasible solutions from values for indicator variables"
212 SCIPdebugMsg(scip, "One-opt found solution candidate with value %g.\n", SCIPgetSolTransObj(scip, sol));
222 SCIPdebugMsg(scip, "Finished one-opt (tried variables: %d, found sols: %d).\n", cnt, *nfoundsols);
253 SCIPdebugMsg(scip, "Trying to generate feasible solution with indicators from solution candidate (obj: %f) ...\n", heurdata->obj);
279 /* Fix binary variables not in cover to 1 and corresponding slack variables to 0. The other binary variables are fixed to 0. */
459 /* The heuristic will only be successful if there are no integral variables and no binary variables except the
464 SCIP_CALL( trySolCandidate(scip, heur, heurdata, heurdata->nindconss, heurdata->indconss, heurdata->solcand, &nfoundsols) );
498 /* The heuristic will only be successful if there are no integral variables and no binary variables except the
530 SCIPdebugMsg(scip, "Trying to improve best solution of value %f.\n", SCIPgetSolOrigObj(scip, bestsol) );
Definition: type_result.h:42
Definition: type_result.h:56
SCIP_RETCODE SCIPincludeHeurIndicator(SCIP *scip)
Definition: heur_indicator.c:552
public methods for SCIP parameter handling
SCIP_RETCODE SCIPbacktrackProbing(SCIP *scip, int probingdepth)
Definition: scip_probing.c:225
Definition: struct_scip.h:68
public methods for memory management
SCIP_CONSHDLR * SCIPfindConshdlr(SCIP *scip, const char *name)
Definition: scip_cons.c:886
SCIP_RETCODE SCIPheurPassIndicator(SCIP *scip, SCIP_HEUR *heur, int nindconss, SCIP_CONS **indconss, SCIP_Bool *solcand, SCIP_Real obj)
Definition: heur_indicator.c:596
Definition: struct_var.h:207
constraint handler for indicator constraints
SCIP_CONS ** SCIPconshdlrGetConss(SCIP_CONSHDLR *conshdlr)
Definition: cons.c:4556
public methods for problem variables
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 SCIPchgVarLbProbing(SCIP *scip, SCIP_VAR *var, SCIP_Real newbound)
Definition: scip_probing.c:301
void SCIPheurSetData(SCIP_HEUR *heur, SCIP_HEURDATA *heurdata)
Definition: heur.c:1371
void SCIPwarningMessage(SCIP *scip, const char *formatstr,...)
Definition: scip_message.c:120
public methods for numerical tolerances
Definition: struct_sol.h:73
public methods for the branch-and-bound tree
#define SCIPduplicateBlockMemoryArray(scip, ptr, source, num)
Definition: scip_mem.h:105
public methods for managing constraints
Definition: type_result.h:44
Definition: struct_cons.h:46
SCIP_RETCODE SCIPsetHeurFree(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURFREE((*heurfree)))
Definition: scip_heur.c:178
SCIP_RETCODE SCIPpropagateProbing(SCIP *scip, int maxproprounds, SCIP_Bool *cutoff, SCIP_Longint *ndomredsfound)
Definition: scip_probing.c:580
Definition: struct_cons.h:126
SCIP_Real SCIPgetSolTransObj(SCIP *scip, SCIP_SOL *sol)
Definition: scip_sol.c:1491
Definition: type_retcode.h:42
public methods for problem copies
public methods for primal CIP solutions
handle partial solutions for linear problems with indicators and otherwise continuous variables ...
SCIP_RETCODE SCIPsolveProbingLP(SCIP *scip, int itlim, SCIP_Bool *lperror, SCIP_Bool *cutoff)
Definition: scip_probing.c:819
Definition: struct_heur.h:97
Definition: type_lp.h:43
public methods for primal heuristic plugins and divesets
public methods for constraint handler plugins and constraints
SCIP_RETCODE SCIPtrySolFree(SCIP *scip, SCIP_SOL **sol, SCIP_Bool printreason, SCIP_Bool completely, SCIP_Bool checkbounds, SCIP_Bool checkintegrality, SCIP_Bool checklprows, SCIP_Bool *stored)
Definition: scip_sol.c:3240
SCIP_VAR * SCIPgetBinaryVarIndicator(SCIP_CONS *cons)
Definition: cons_indicator.c:8112
public methods for the LP relaxation, rows and columns
static SCIP_RETCODE tryOneOpt(SCIP *scip, SCIP_HEUR *heur, SCIP_HEURDATA *heurdata, int nindconss, SCIP_CONS **indconss, SCIP_Bool *solcand, int *nfoundsols)
Definition: heur_indicator.c:93
general public methods
public methods for solutions
public methods for the probing mode
public methods for message output
SCIP_RETCODE SCIPsetHeurInit(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURINIT((*heurinit)))
Definition: scip_heur.c:194
public methods for message handling
static SCIP_RETCODE trySolCandidate(SCIP *scip, SCIP_HEUR *heur, SCIP_HEURDATA *heurdata, int nindconss, SCIP_CONS **indconss, SCIP_Bool *solcand, int *nfoundsols)
Definition: heur_indicator.c:230
SCIP_RETCODE SCIPsetHeurCopy(SCIP *scip, SCIP_HEUR *heur, SCIP_DECL_HEURCOPY((*heurcopy)))
Definition: scip_heur.c:162
#define SCIPfreeBlockMemoryArrayNull(scip, ptr, num)
Definition: scip_mem.h:111
SCIP_Bool SCIPisFeasIntegral(SCIP *scip, SCIP_Real val)
Definition: scip_numerics.c:883
public methods for primal heuristics
Definition: objbenders.h:43
public methods for global and local (sub)problems
SCIP_RETCODE SCIPchgVarUbProbing(SCIP *scip, SCIP_VAR *var, SCIP_Real newbound)
Definition: scip_probing.c:345
SCIP_Real SCIPgetSolVal(SCIP *scip, SCIP_SOL *sol, SCIP_VAR *var)
Definition: scip_sol.c:1361
SCIP_RETCODE SCIPaddBoolParam(SCIP *scip, const char *name, const char *desc, SCIP_Bool *valueptr, SCIP_Bool isadvanced, SCIP_Bool defaultvalue, SCIP_DECL_PARAMCHGD((*paramchgd)), SCIP_PARAMDATA *paramdata)
Definition: scip_param.c:57
SCIP_RETCODE SCIPcreateSol(SCIP *scip, SCIP_SOL **sol, SCIP_HEUR *heur)
Definition: scip_sol.c:328
memory allocation routines
SCIP_RETCODE SCIPprintSol(SCIP *scip, SCIP_SOL *sol, FILE *file, SCIP_Bool printzeros)
Definition: scip_sol.c:1775