Scippy

SCIP

Solving Constraint Integer Programs

heur_proximity.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) 2002-2020 Konrad-Zuse-Zentrum */
7 /* fuer Informationstechnik Berlin */
8 /* */
9 /* SCIP is distributed under the terms of the ZIB Academic License. */
10 /* */
11 /* You should have received a copy of the ZIB Academic License */
12 /* along with SCIP; see the file COPYING. If not visit scipopt.org. */
13 /* */
14 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
15 
16 /**@file heur_proximity.h
17  * @ingroup PRIMALHEURISTICS
18  * @brief improvement heuristic which uses an auxiliary objective instead of the original objective function which
19  * is itself added as a constraint to a sub-SCIP instance. The heuristic was presented by Matteo Fischetti
20  * and Michele Monaci
21  * @author Gregor Hendel
22  */
23 
24 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
25 
26 #ifndef __SCIP_HEUR_PROXIMITY_H__
27 #define __SCIP_HEUR_PROXIMITY_H__
28 
29 #include "scip/def.h"
30 #include "scip/type_heur.h"
31 #include "scip/type_result.h"
32 #include "scip/type_retcode.h"
33 #include "scip/type_scip.h"
34 
35 #ifdef __cplusplus
36 extern "C" {
37 #endif
38 
39 /** creates the proximity primal heuristic and includes it in SCIP
40  *
41  * @ingroup PrimalHeuristicIncludes
42  */
45  SCIP* scip /**< SCIP data structure */
46  );
47 
48 /**@addtogroup PRIMALHEURISTICS
49  *
50  * @{
51  */
52 
53 /** main procedure of the proximity heuristic, creates and solves a sub-SCIP
54  *
55  * @note the method can be applied in an iterative way, keeping the same subscip in between. If the @p freesubscip
56  * parameter is set to FALSE, the heuristic will keep the subscip data structures. Always set this parameter
57  * to TRUE, or call SCIPdeleteSubproblemProximity() afterwards
58  */
61  SCIP* scip, /**< original SCIP data structure */
62  SCIP_HEUR* heur, /**< heuristic data structure */
63  SCIP_RESULT* result, /**< result data structure */
64  SCIP_Real minimprove, /**< factor by which proximity should at least improve the incumbent */
65  SCIP_Longint nnodes, /**< node limit for the subproblem */
66  SCIP_Longint nlpiters, /**< LP iteration limit for the subproblem */
67  SCIP_Longint* nusednodes, /**< pointer to store number of used nodes in subscip */
68  SCIP_Longint* nusedlpiters, /**< pointer to store number of used LP iterations in subscip */
69  SCIP_Bool freesubscip /**< should the created sub-MIP be freed at the end of the method? */
70  );
71 
72 /** frees the sub-MIP created by proximity */
75  SCIP* scip /** SCIP data structure */
76  );
77 
78 /** @} */
79 
80 #ifdef __cplusplus
81 }
82 #endif
83 
84 #endif
enum SCIP_Result SCIP_RESULT
Definition: type_result.h:52
SCIP_EXPORT SCIP_RETCODE SCIPincludeHeurProximity(SCIP *scip)
#define SCIP_EXPORT
Definition: def.h:100
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:54
type definitions for return codes for SCIP methods
type definitions for primal heuristics
type definitions for SCIP&#39;s main datastructure
#define SCIP_Bool
Definition: def.h:70
#define SCIP_Real
Definition: def.h:163
result codes for SCIP callback methods
#define SCIP_Longint
Definition: def.h:148
#define nnodes
Definition: gastrans.c:65
common defines and data types used in all packages of SCIP
SCIP_EXPORT SCIP_RETCODE SCIPdeleteSubproblemProximity(SCIP *scip)
SCIP_EXPORT SCIP_RETCODE SCIPapplyProximity(SCIP *scip, SCIP_HEUR *heur, SCIP_RESULT *result, SCIP_Real minimprove, SCIP_Longint nnodes, SCIP_Longint nlpiters, SCIP_Longint *nusednodes, SCIP_Longint *nusedlpiters, SCIP_Bool freesubscip)