Scippy

SCIP

Solving Constraint Integer Programs

heur_linesearchdiving.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) 2002-2022 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_linesearchdiving.h
17  * @ingroup PRIMALHEURISTICS
18  * @brief LP diving heuristic that fixes variables with a large difference to their root solution
19  * @author Tobias Achterberg
20  *
21  * Diving heuristic: Iteratively fixes some fractional variable and resolves the LP-relaxation, thereby simulating a
22  * depth-first-search in the tree. Line search diving chooses the variable with the greatest difference of its root LP
23  * solution and the current LP solution, hence, the variable that developed most. It is fixed to the next integer in
24  * the direction it developed. One-level backtracking is applied: If the LP gets infeasible, the last fixing is undone,
25  * and the opposite fixing is tried. If this is infeasible, too, the procedure aborts.
26  */
27 
28 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
29 
30 #ifndef __SCIP_HEUR_LINESEARCHDIVING_H__
31 #define __SCIP_HEUR_LINESEARCHDIVING_H__
32 
33 #include "scip/def.h"
34 #include "scip/type_retcode.h"
35 #include "scip/type_scip.h"
36 
37 #ifdef __cplusplus
38 extern "C" {
39 #endif
40 
41 /** creates the linesearchdiving primal heuristic and includes it in SCIP
42  *
43  * @ingroup PrimalHeuristicIncludes
44  */
45 SCIP_EXPORT
47  SCIP* scip /**< SCIP data structure */
48  );
49 
50 #ifdef __cplusplus
51 }
52 #endif
53 
54 #endif
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:54
type definitions for return codes for SCIP methods
type definitions for SCIP&#39;s main datastructure
SCIP_RETCODE SCIPincludeHeurLinesearchdiving(SCIP *scip)
common defines and data types used in all packages of SCIP