/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* */ /* 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 sepa_aggregation.h * @ingroup SEPARATORS * @brief flow cover and complemented mixed integer rounding cuts separator (Marchand's version) * @author Leona Gottwald * @author Kati Wolter * @author Tobias Achterberg * * For an overview see: * * Marchand, H., & Wolsey, L. A. (2001).@n * Aggregation and mixed integer rounding to solve MIPs.@n * Operations research, 49(3), 363-371. * * Some remarks: * - In general, continuous variables are less prefered than integer variables, since their cut * coefficient is worse. * - We seek for aggregations that project out continuous variables that are far away from their bound, * since if it is at its bound then it doesn't contribute to the violation * - These aggregations are also useful for the flowcover separation, so after building an aggregation * we try to generate a MIR cut and a flowcover cut. * - We only keep the best cut. */ /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ #ifndef __SCIP_SEPA_CMIR_H__ #define __SCIP_SEPA_CMIR_H__ #include "scip/def.h" #include "scip/type_retcode.h" #include "scip/type_scip.h" #ifdef __cplusplus extern "C" { #endif /** creates the aggregation separator and includes it in SCIP * * @ingroup SeparatorIncludes */ SCIP_EXPORT SCIP_RETCODE SCIPincludeSepaAggregation( SCIP* scip /**< SCIP data structure */ ); #ifdef __cplusplus } #endif #endif