SCIP

Solving Constraint Integer Programs

heur_zirounding.h
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1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
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6 /* Copyright (c) 2002-2024 Zuse Institute Berlin (ZIB) */
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23 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24
25 /**@file heur_zirounding.h
26  * @ingroup PRIMALHEURISTICS
27  * @brief ZI Round primal heuristic
28  * @author Gregor Hendel
29  *
30  * ZI Round (C. Wallace, Journal of Heuristics 2009) reduces the integer infeasibility of an LP solution step-by-step by
31  * shifting fractional values towards integrality, but not necessarily rounding them. For each integer variable with
32  * fractional solution value, the heuristic calculates bounds for both possible rounding directions such that the
33  * obtained solution stays LP-feasible. The solution value is then shifted by the corresponding bound into the direction
34  * which reduces the fractionality most.
35  */
36
37 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
38
39 #ifndef __SCIP_HEUR_ZIROUNDING_H__
40 #define __SCIP_HEUR_ZIROUNDING_H__
41
42 #include "scip/def.h"
43 #include "scip/type_retcode.h"
44 #include "scip/type_scip.h"
45
46 #ifdef __cplusplus
47 extern "C" {
48 #endif
49
50 /** creates the zirounding primal heuristic and includes it in SCIP
51  *
52  * @ingroup PrimalHeuristicIncludes
53  */
54 SCIP_EXPORT
56  SCIP* scip /**< SCIP data structure */
57  );
58
59 #ifdef __cplusplus
60 }
61 #endif
62
63 #endif
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
type definitions for return codes for SCIP methods
SCIP_RETCODE SCIPincludeHeurZirounding(SCIP *scip)
type definitions for SCIP&#39;s main datastructure
common defines and data types used in all packages of SCIP