sepa_aggregation.h 2.55 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*                                                                           */
/*                  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