62#define HEUR_NAME "dins"
63#define HEUR_DESC "distance induced neighborhood search by Ghosh"
64#define HEUR_DISPCHAR SCIP_HEURDISPCHAR_LNS
65#define HEUR_PRIORITY -1105000
68#define HEUR_MAXDEPTH -1
69#define HEUR_TIMING SCIP_HEURTIMING_AFTERLPNODE
70#define HEUR_USESSUBSCIP TRUE
72#define DEFAULT_NODESOFS 5000LL
73#define DEFAULT_MAXNODES 5000LL
74#define DEFAULT_MINNODES 50LL
75#define DEFAULT_MINIMPROVE 0.01
76#define DEFAULT_NODESQUOT 0.05
77#define DEFAULT_LPLIMFAC 1.5
78#define DEFAULT_MINFIXINGRATE 0.3
79#define DEFAULT_NWAITINGNODES 200LL
80#define DEFAULT_NEIGHBORHOODSIZE 18
81#define DEFAULT_SOLNUM 5
82#define DEFAULT_USELPROWS FALSE
84#define DEFAULT_COPYCUTS TRUE
87#define DEFAULT_BESTSOLLIMIT 3
88#define DEFAULT_USEUCT FALSE
92#define EVENTHDLR_NAME "Dins"
93#define EVENTHDLR_DESC "LP event handler for " HEUR_NAME " heuristic"
102 SCIP_Longint nodesofs;
103 SCIP_Longint maxnodes;
104 SCIP_Longint minnodes;
105 SCIP_Real minfixingrate;
106 SCIP_Longint nwaitingnodes;
107 SCIP_Real minimprove;
109 SCIP_Longint lastnsolsfound;
113 int neighborhoodsize;
159 if(
REALABS(lpsol - mipsol) >= 0.5 )
167 range = 2*lpsol-mipsol;
169 if( mipsol >= lpsol )
172 *lbptr =
MAX(*lbptr, range);
183 *ubptr =
MIN(*ubptr, range);
193 *lbptr =
MAX(*lbptr, lbglobal);
194 *ubptr =
MIN(*ubptr, ubglobal);
199 *lbptr =
MAX(mipsol, lbglobal);
200 *ubptr =
MIN(mipsol, ubglobal);
212 SCIP_Real* fixedvals,
269 *intfixings = *binfixings = 0;
274 SCIP_Real rootlpsolval;
301 fixedvars[nfixedvars] =
vars[
i];
302 fixedvals[nfixedvars] = mipsolval;
308 *binfixings = nfixedvars;
323 fixedvars[(nfixedvars)] =
vars[
i];
324 fixedvals[(nfixedvars)] = lb;
329 *intfixings = nfixedvars - *binfixings;
352 if( subvars[
i] ==
NULL )
416 if( subvars[
i] ==
NULL )
429 consvals[nconsvars] = -1.0;
434 consvals[nconsvars] = 1.0;
435 consvars[nconsvars++] = subvars[
i];
440 lhs, rhs,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
FALSE,
FALSE,
TRUE,
TRUE,
FALSE) );
463 SCIP_Real* fixedvals,
470 SCIP_Longint nsubnodes
476 SCIP_Real upperbound;
497 if( eventhdlr ==
NULL )
503 SCIPdebugMsg(
scip,
"Copying the SCIP instance was %ssuccessful.\n", success ?
"" :
"not ");
505 SCIPdebugMsg(
scip,
"DINS subproblem: %d vars (%d binvars & %d intvars), %d cons\n",
793 SCIP_Real* fixedvals;
795 SCIP_Longint maxnnodes;
796 SCIP_Longint nsubnodes;
852 nsubnodes = maxnnodes -
heurdata->usednodes;
856 if( nsubnodes < heurdata->minnodes )
883 binfixings = intfixings = 0;
900 retcode =
wrapperDins(
scip, subscip, heur,
heurdata,
vars, fixedvars, fixedvals,
result,
nvars,
nbinvars,
nintvars, binfixings, intfixings, nsubnodes);
943 "number of nodes added to the contingent of the total nodes",
946 "contingent of sub problem nodes in relation to the number of nodes of the original problem",
949 "minimum number of nodes required to start the subproblem",
952 "number of pool-solutions to be checked for flag array update (for hard fixing of binary variables)",
955 "radius (using Manhattan metric) of the incumbent's neighborhood to be searched",
958 "maximum number of nodes to regard in the subproblem",
961 "factor by which " HEUR_NAME " should at least improve the incumbent",
964 "number of nodes without incumbent change that heuristic should wait",
968 "factor by which the limit on the number of LP depends on the node limit",
972 "minimum percentage of integer variables that have to be fixable",
976 "should subproblem be created out of the rows in the LP rows?",
980 "if uselprows == FALSE, should all active cuts from cutpool be copied to constraints in subproblem?",
984 "should uct node selection be used at the beginning of the search?",
988 "limit on number of improving incumbent solutions in sub-CIP",
Constraint handler for linear constraints in their most general form, .
#define SCIP_CALL_ABORT(x)
#define SCIP_LONGINT_FORMAT
SCIP_RETCODE SCIPcreateConsLinear(SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars, SCIP_Real *vals, SCIP_Real lhs, SCIP_Real rhs, SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, SCIP_Bool modifiable, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode)
SCIP_RETCODE SCIPtranslateSubSols(SCIP *scip, SCIP *subscip, SCIP_HEUR *heur, SCIP_VAR **subvars, SCIP_Bool *success, int *solindex)
SCIP_RETCODE SCIPcheckCopyLimits(SCIP *sourcescip, SCIP_Bool *success)
SCIP_RETCODE SCIPcopyLimits(SCIP *sourcescip, SCIP *targetscip)
SCIP_Bool SCIPisStopped(SCIP *scip)
SCIP_RETCODE SCIPfree(SCIP **scip)
SCIP_RETCODE SCIPcreate(SCIP **scip)
int SCIPgetNIntVars(SCIP *scip)
const char * SCIPgetProbName(SCIP *scip)
SCIP_RETCODE SCIPsetObjlimit(SCIP *scip, SCIP_Real objlimit)
SCIP_RETCODE SCIPgetVarsData(SCIP *scip, SCIP_VAR ***vars, int *nvars, int *nbinvars, int *nintvars, int *nimplvars, int *ncontvars)
int SCIPgetNVars(SCIP *scip)
SCIP_RETCODE SCIPaddCons(SCIP *scip, SCIP_CONS *cons)
int SCIPgetNConss(SCIP *scip)
int SCIPgetNBinVars(SCIP *scip)
void SCIPhashmapFree(SCIP_HASHMAP **hashmap)
void * SCIPhashmapGetImage(SCIP_HASHMAP *hashmap, void *origin)
SCIP_RETCODE SCIPhashmapCreate(SCIP_HASHMAP **hashmap, BMS_BLKMEM *blkmem, int mapsize)
SCIP_RETCODE SCIPaddLongintParam(SCIP *scip, const char *name, const char *desc, SCIP_Longint *valueptr, SCIP_Bool isadvanced, SCIP_Longint defaultvalue, SCIP_Longint minvalue, SCIP_Longint maxvalue, SCIP_DECL_PARAMCHGD((*paramchgd)), SCIP_PARAMDATA *paramdata)
SCIP_Bool SCIPisParamFixed(SCIP *scip, const char *name)
SCIP_RETCODE SCIPaddIntParam(SCIP *scip, const char *name, const char *desc, int *valueptr, SCIP_Bool isadvanced, int defaultvalue, int minvalue, int maxvalue, SCIP_DECL_PARAMCHGD((*paramchgd)), SCIP_PARAMDATA *paramdata)
SCIP_RETCODE SCIPsetLongintParam(SCIP *scip, const char *name, SCIP_Longint value)
SCIP_RETCODE SCIPaddRealParam(SCIP *scip, const char *name, const char *desc, SCIP_Real *valueptr, SCIP_Bool isadvanced, SCIP_Real defaultvalue, SCIP_Real minvalue, SCIP_Real maxvalue, SCIP_DECL_PARAMCHGD((*paramchgd)), SCIP_PARAMDATA *paramdata)
SCIP_RETCODE SCIPsetIntParam(SCIP *scip, const char *name, int value)
SCIP_RETCODE SCIPsetSubscipsOff(SCIP *scip, SCIP_Bool quiet)
SCIP_RETCODE SCIPsetPresolving(SCIP *scip, SCIP_PARAMSETTING paramsetting, SCIP_Bool quiet)
SCIP_RETCODE SCIPsetCharParam(SCIP *scip, const char *name, char value)
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)
SCIP_RETCODE SCIPsetBoolParam(SCIP *scip, const char *name, SCIP_Bool value)
SCIP_RETCODE SCIPsetSeparating(SCIP *scip, SCIP_PARAMSETTING paramsetting, SCIP_Bool quiet)
SCIP_RETCODE SCIPincludeHeurDins(SCIP *scip)
SCIP_BRANCHRULE * SCIPfindBranchrule(SCIP *scip, const char *name)
SCIP_RETCODE SCIPreleaseCons(SCIP *scip, SCIP_CONS **cons)
SCIP_RETCODE SCIPincludeEventhdlrBasic(SCIP *scip, SCIP_EVENTHDLR **eventhdlrptr, const char *name, const char *desc, SCIP_DECL_EVENTEXEC((*eventexec)), SCIP_EVENTHDLRDATA *eventhdlrdata)
const char * SCIPeventhdlrGetName(SCIP_EVENTHDLR *eventhdlr)
SCIP_EVENTTYPE SCIPeventGetType(SCIP_EVENT *event)
SCIP_RETCODE SCIPcatchEvent(SCIP *scip, SCIP_EVENTTYPE eventtype, SCIP_EVENTHDLR *eventhdlr, SCIP_EVENTDATA *eventdata, int *filterpos)
SCIP_RETCODE SCIPdropEvent(SCIP *scip, SCIP_EVENTTYPE eventtype, SCIP_EVENTHDLR *eventhdlr, SCIP_EVENTDATA *eventdata, int filterpos)
SCIP_RETCODE SCIPsetHeurFree(SCIP *scip, SCIP_HEUR *heur,)
SCIP_HEURDATA * SCIPheurGetData(SCIP_HEUR *heur)
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)
SCIP_RETCODE SCIPsetHeurInitsol(SCIP *scip, SCIP_HEUR *heur,)
SCIP_Longint SCIPheurGetNBestSolsFound(SCIP_HEUR *heur)
SCIP_RETCODE SCIPsetHeurCopy(SCIP *scip, SCIP_HEUR *heur,)
SCIP_Longint SCIPheurGetNCalls(SCIP_HEUR *heur)
SCIP_RETCODE SCIPsetHeurExitsol(SCIP *scip, SCIP_HEUR *heur,)
const char * SCIPheurGetName(SCIP_HEUR *heur)
void SCIPheurSetData(SCIP_HEUR *heur, SCIP_HEURDATA *heurdata)
SCIP_Bool SCIPhasCurrentNodeLP(SCIP *scip)
SCIP_LPSOLSTAT SCIPgetLPSolstat(SCIP *scip)
SCIP_Real SCIPgetLPObjval(SCIP *scip)
#define SCIPfreeBlockMemoryArray(scip, ptr, num)
int SCIPcalcMemGrowSize(SCIP *scip, int num)
#define SCIPallocBufferArray(scip, ptr, num)
#define SCIPfreeBufferArray(scip, ptr)
#define SCIPallocBlockMemoryArray(scip, ptr, num)
#define SCIPreallocBlockMemoryArray(scip, ptr, oldnum, newnum)
#define SCIPfreeBlockMemory(scip, ptr)
#define SCIPallocBlockMemory(scip, ptr)
SCIP_NODESEL * SCIPfindNodesel(SCIP *scip, const char *name)
SCIP_SOL * SCIPgetBestSol(SCIP *scip)
SCIP_HEUR * SCIPgetSolHeur(SCIP *scip, SCIP_SOL *sol)
int SCIPgetNSols(SCIP *scip)
SCIP_Longint SCIPgetSolNodenum(SCIP *scip, SCIP_SOL *sol)
SCIP_SOL ** SCIPgetSols(SCIP *scip)
SCIP_Real SCIPgetSolVal(SCIP *scip, SCIP_SOL *sol, SCIP_VAR *var)
SCIP_RETCODE SCIPtransformProb(SCIP *scip)
SCIP_RETCODE SCIPinterruptSolve(SCIP *scip)
SCIP_RETCODE SCIPsolve(SCIP *scip)
SCIP_Longint SCIPgetNSolsFound(SCIP *scip)
SCIP_Real SCIPgetUpperbound(SCIP *scip)
SCIP_Longint SCIPgetNNodes(SCIP *scip)
SCIP_RETCODE SCIPprintStatistics(SCIP *scip, FILE *file)
SCIP_Real SCIPgetLowerbound(SCIP *scip)
SCIP_Longint SCIPgetNLPs(SCIP *scip)
SCIP_Real SCIPgetCutoffbound(SCIP *scip)
SCIP_RETCODE SCIPcopyLargeNeighborhoodSearch(SCIP *sourcescip, SCIP *subscip, SCIP_HASHMAP *varmap, const char *suffix, SCIP_VAR **fixedvars, SCIP_Real *fixedvals, int nfixedvars, SCIP_Bool uselprows, SCIP_Bool copycuts, SCIP_Bool *success, SCIP_Bool *valid)
SCIP_Bool SCIPisGE(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
SCIP_Bool SCIPisFeasEQ(SCIP *scip, SCIP_Real val1, SCIP_Real val2)
SCIP_Real SCIPfeasCeil(SCIP *scip, SCIP_Real val)
SCIP_Real SCIPfeasFloor(SCIP *scip, SCIP_Real val)
SCIP_Bool SCIPisInfinity(SCIP *scip, SCIP_Real val)
SCIP_Bool SCIPisFeasIntegral(SCIP *scip, SCIP_Real val)
SCIP_Real SCIPsumepsilon(SCIP *scip)
SCIP_VARTYPE SCIPvarGetType(SCIP_VAR *var)
SCIP_Real SCIPvarGetUbGlobal(SCIP_VAR *var)
SCIP_Real SCIPvarGetRootSol(SCIP_VAR *var)
SCIP_RETCODE SCIPchgVarLbGlobal(SCIP *scip, SCIP_VAR *var, SCIP_Real newbound)
SCIP_Real SCIPvarGetLPSol(SCIP_VAR *var)
SCIP_RETCODE SCIPchgVarUbGlobal(SCIP *scip, SCIP_VAR *var, SCIP_Real newbound)
SCIP_Real SCIPvarGetLbGlobal(SCIP_VAR *var)
int SCIPsnprintf(char *t, int len, const char *s,...)
#define DEFAULT_NODESQUOT
#define DEFAULT_NWAITINGNODES
static SCIP_RETCODE determineVariableFixings(SCIP *scip, SCIP_HEUR *heur, SCIP_HEURDATA *heurdata, SCIP_VAR **vars, SCIP_VAR **fixedvars, SCIP_Real *fixedvals, int nbinvars, int nintvars, int *binfixings, int *intfixings)
#define DEFAULT_NEIGHBORHOODSIZE
#define DEFAULT_MINFIXINGRATE
#define DEFAULT_MINIMPROVE
#define DEFAULT_USELPROWS
#define DEFAULT_BESTSOLLIMIT
static void computeIntegerVariableBounds(SCIP *scip, SCIP_VAR *var, SCIP_Real *lbptr, SCIP_Real *ubptr)
static SCIP_RETCODE addLocalBranchingConstraint(SCIP *scip, SCIP *subscip, SCIP_VAR **subvars, SCIP_HEURDATA *heurdata)
static SCIP_RETCODE reboundIntegerVariables(SCIP *scip, SCIP *subscip, SCIP_VAR **vars, SCIP_VAR **subvars, int nbinvars, int nintvars)
static SCIP_RETCODE wrapperDins(SCIP *scip, SCIP *subscip, SCIP_HEUR *heur, SCIP_HEURDATA *heurdata, SCIP_VAR **vars, SCIP_VAR **fixedvars, SCIP_Real *fixedvals, SCIP_RESULT *result, int nvars, int nbinvars, int nintvars, int binfixings, int intfixings, SCIP_Longint nsubnodes)
assert(minobj< SCIPgetCutoffbound(scip))
methods commonly used by primal heuristics
memory allocation routines
BMS_BLKMEM * SCIPblkmem(SCIP *scip)
public methods for managing events
public methods for primal heuristics
public methods for message output
public data structures and miscellaneous methods
public methods for problem variables
public methods for branching rule plugins and branching
public methods for constraint handler plugins and constraints
public methods for problem copies
public methods for event handler plugins and event handlers
public methods for primal heuristic plugins and divesets
public methods for the LP relaxation, rows and columns
public methods for memory management
public methods for message handling
public methods for node selector plugins
public methods for numerical tolerances
public methods for SCIP parameter handling
public methods for global and local (sub)problems
public methods for solutions
public methods for querying solving statistics
public methods for SCIP variables
struct SCIP_EventData SCIP_EVENTDATA
#define SCIP_DECL_EVENTEXEC(x)
#define SCIP_EVENTTYPE_LPSOLVED
#define SCIP_DECL_HEURINITSOL(x)
#define SCIP_DECL_HEURCOPY(x)
struct SCIP_HeurData SCIP_HEURDATA
#define SCIP_DECL_HEURFREE(x)
#define SCIP_DECL_HEUREXITSOL(x)
#define SCIP_DECL_HEUREXEC(x)
enum SCIP_Result SCIP_RESULT
enum SCIP_Retcode SCIP_RETCODE