/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* */ /* This file is part of the program and library */ /* SCIP --- Solving Constraint Integer Programs */ /* */ /* Copyright (C) 2002-2020 Konrad-Zuse-Zentrum */ /* fuer Informationstechnik Berlin */ /* */ /* SCIP is distributed under the terms of the ZIB Academic License. */ /* */ /* You should have received a copy of the ZIB Academic License */ /* along with SCIP; see the file COPYING. If not visit scipopt.org. */ /* */ /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /**@file heur_undercover.h * @ingroup PRIMALHEURISTICS * @brief Undercover primal heuristic for MINLPs * @author Timo Berthold * @author Ambros Gleixner * * The undercover heuristic is designed for mixed-integer nonlinear programs and tries to fix a subset of variables such * as to make each constraint linear or convex. For this purpose it solves a binary program to automatically determine * the minimum number of variable fixings necessary. As fixing values, we use values from the LP relaxation, the NLP * relaxation, or the incumbent solution. */ /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ #ifndef __SCIP_HEUR_UNDERCOVER_H__ #define __SCIP_HEUR_UNDERCOVER_H__ #include "scip/def.h" #include "scip/type_retcode.h" #include "scip/type_scip.h" #include "scip/type_var.h" #ifdef __cplusplus extern "C" { #endif /** creates the undercover primal heuristic and includes it in SCIP * * @ingroup PrimalHeuristicIncludes */ SCIP_EXPORT SCIP_RETCODE SCIPincludeHeurUndercover( SCIP* scip /**< SCIP data structure */ ); /**@addtogroup PRIMALHEURISTICS * * @{ */ /** computes a minimal set of covering variables */ SCIP_EXPORT SCIP_RETCODE SCIPcomputeCoverUndercover( SCIP* scip, /**< SCIP data structure */ int* coversize, /**< size of the computed cover */ SCIP_VAR** cover, /**< pointer to store the variables (of the original SCIP) in the computed cover * (should be ready to hold SCIPgetNVars(scip) entries) */ SCIP_Real timelimit, /**< time limit */ SCIP_Real memorylimit, /**< memory limit */ SCIP_Real objlimit, /**< objective limit: upper bound on coversize */ SCIP_Bool globalbounds, /**< should global bounds on variables be used instead of local bounds at focus node? */ SCIP_Bool onlyconvexify, /**< should we only fix/dom.red. variables creating nonconvexity? */ SCIP_Bool coverbd, /**< should bounddisjunction constraints be covered (or just copied)? */ char coveringobj, /**< objective function of the covering problem ('b'ranching status, * influenced nonlinear 'c'onstraints/'t'erms, 'd'omain size, 'l'ocks, * 'm'in of up/down locks, 'u'nit penalties, constraint 'v'iolation) */ SCIP_Bool* success /**< feasible cover found? */ ); /** @} */ #ifdef __cplusplus } #endif #endif