Scippy

SCIP

Solving Constraint Integer Programs

sepa_aggregation.h
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1/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2/* */
3/* This file is part of the program and library */
4/* SCIP --- Solving Constraint Integer Programs */
5/* */
6/* Copyright (c) 2002-2024 Zuse Institute Berlin (ZIB) */
7/* */
8/* Licensed under the Apache License, Version 2.0 (the "License"); */
9/* you may not use this file except in compliance with the License. */
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21/* along with SCIP; see the file LICENSE. If not visit scipopt.org. */
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23/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24
25/**@file sepa_aggregation.h
26 * @ingroup SEPARATORS
27 * @brief flow cover and complemented mixed integer rounding cuts separator (Marchand's version)
28 * @author Leona Gottwald
29 * @author Kati Wolter
30 * @author Tobias Achterberg
31 *
32 * For an overview see:
33 *
34 * Marchand, H., & Wolsey, L. A. (2001).@n
35 * Aggregation and mixed integer rounding to solve MIPs.@n
36 * Operations research, 49(3), 363-371.
37 *
38 * Some remarks:
39 * - In general, continuous variables are less prefered than integer variables, since their cut
40 * coefficient is worse.
41 * - We seek for aggregations that project out continuous variables that are far away from their bound,
42 * since if it is at its bound then it doesn't contribute to the violation
43 * - These aggregations are also useful for the flowcover separation, so after building an aggregation
44 * we try to generate a MIR cut and a flowcover cut.
45 * - We only keep the best cut.
46 */
47
48/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
49
50#ifndef __SCIP_SEPA_CMIR_H__
51#define __SCIP_SEPA_CMIR_H__
52
53
54#include "scip/def.h"
55#include "scip/type_retcode.h"
56#include "scip/type_scip.h"
57
58#ifdef __cplusplus
59extern "C" {
60#endif
61
62/** creates the aggregation separator and includes it in SCIP
63 *
64 * @ingroup SeparatorIncludes
65 */
66SCIP_EXPORT
68 SCIP* scip /**< SCIP data structure */
69 );
70
71#ifdef __cplusplus
72}
73#endif
74
75#endif
common defines and data types used in all packages of SCIP
SCIP_RETCODE SCIPincludeSepaAggregation(SCIP *scip)
type definitions for return codes for SCIP methods
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
type definitions for SCIP's main datastructure