# SCIP

Solving Constraint Integer Programs

heur_twoopt.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 /* */
7 /* fuer Informationstechnik Berlin */
8 /* */
10 /* */
12 /* along with SCIP; see the file COPYING. If not visit scipopt.org. */
13 /* */
14 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
15
16 /**@file heur_twoopt.h
17  * @ingroup PRIMALHEURISTICS
18  * @brief Primal heuristic to improve incumbent solution by flipping pairs of variables
19  * @author Timo Berthold
20  * @author Gregor Hendel
21  *
22  * The Twoopt heuristic attempts to improve a feasible MIP solution by altering the solution values of pairs of
23  * variables. Only variables which share a pre-defined ratio of LP rows are considered as pairs. Each step of the
24  * heuristic consists of improving the objective value by shifting one variable, and then compensating the resulting
25  * infeasibilities by shifting a second variable, without completely losing the objective improvement. Similarly to
26  * Oneopt (see @ref heur_oneopt.h), pairs are processed in non-decreasing order of their impact on the objective.
27  */
28
29 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
30
31 #ifndef __SCIP_HEUR_TWOOPT_H__
32 #define __SCIP_HEUR_TWOOPT_H__
33
34 #include "scip/def.h"
35 #include "scip/type_retcode.h"
36 #include "scip/type_scip.h"
37
38 #ifdef __cplusplus
39 extern "C" {
40 #endif
41
42 /** creates the twoopt primal heuristic and includes it in SCIP
43  *
44  * @ingroup PrimalHeuristicIncludes
45  */
48  SCIP* scip /**< SCIP data structure */
49  );
50
51 #ifdef __cplusplus
52 }
53 #endif
54
55 #endif
#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 SCIP&#39;s main datastructure
common defines and data types used in all packages of SCIP
SCIP_EXPORT SCIP_RETCODE SCIPincludeHeurTwoopt(SCIP *scip)
Definition: heur_twoopt.c:1769