Scippy

SCIP

Solving Constraint Integer Programs

heur_proximity.h
Go to the documentation of this file.
1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
5 /* */
6 /* Copyright (C) 2002-2015 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 email to scip@zib.de. */
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 
30 #include "scip/scip.h"
31 
32 #ifdef __cplusplus
33 extern "C" {
34 #endif
35 
36 /** main procedure of the proximity heuristic, creates and solves a sub-SCIP
37  *
38  * @note the method can be applied in an iterative way, keeping the same subscip in between. If the @p freesubscip
39  * parameter is set to FALSE, the heuristic will keep the subscip data structures. Always set this parameter
40  * to TRUE, or call SCIPdeleteSubproblemProximity() afterwards
41  */
43  SCIP* scip, /**< original SCIP data structure */
44  SCIP_HEUR* heur, /**< heuristic data structure */
45  SCIP_RESULT* result, /**< result data structure */
46  SCIP_Real minimprove, /**< factor by which proximity should at least improve the incumbent */
47  SCIP_Longint nnodes, /**< node limit for the subproblem */
48  SCIP_Longint nlpiters, /**< LP iteration limit for the subproblem */
49  SCIP_Longint* nusednodes, /**< pointer to store number of used nodes in subscip */
50  SCIP_Longint* nusedlpiters, /**< pointer to store number of used LP iterations in subscip */
51  SCIP_Bool freesubscip /**< should the created sub-MIP be freed at the end of the method? */
52  );
53 
54 /** creates the proximity primal heuristic and includes it in SCIP */
55 extern
57  SCIP* scip /**< SCIP data structure */
58  );
59 
60 /** frees the sub-MIP created by proximity */
62  SCIP* scip /** SCIP data structure */
63  );
64 
65 #ifdef __cplusplus
66 }
67 #endif
68 
69 #endif
enum SCIP_Result SCIP_RESULT
Definition: type_result.h:51
SCIP_RETCODE SCIPincludeHeurProximity(SCIP *scip)
struct SCIP_Heur SCIP_HEUR
Definition: type_heur.h:50
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:53
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)
struct Scip SCIP
Definition: type_scip.h:30
#define SCIP_Bool
Definition: def.h:50
#define SCIP_Real
Definition: def.h:124
#define SCIP_Longint
Definition: def.h:109
SCIP_RETCODE SCIPdeleteSubproblemProximity(SCIP *scip)
SCIP callable library.