Scippy

SCIP

Solving Constraint Integer Programs

heur_oneopt.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 2002-2022 Zuse Institute Berlin */
7 /* */
8 /* Licensed under the Apache License, Version 2.0 (the "License"); */
9 /* you may not use this file except in compliance with the License. */
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19 /* */
20 /* You should have received a copy of the Apache-2.0 license */
21 /* along with SCIP; see the file LICENSE. If not visit scipopt.org. */
22 /* */
23 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24 
25 /**@file heur_oneopt.h
26  * @ingroup PRIMALHEURISTICS
27  * @brief Improvement heuristic that alters single variable values
28  * @author Timo Berthold
29  *
30  * Oneopt is a straightforward improvement heuristic: given a feasible MIP solution, the value of
31  * an integer variable x<sub>j</sub> can be decreased for c<sub>j</sub> > 0 or increased for c<sub>j</sub> < 0
32  * if the resulting solution is still feasible. If more than one variable can be shifted, they are sorted by
33  * non-decreasing impact on the objective and sequentially shifted until no more improvements can be
34  * obtained.
35  */
36 
37 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
38 
39 #ifndef __SCIP_HEUR_ONEOPT_H__
40 #define __SCIP_HEUR_ONEOPT_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 oneopt 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
type definitions for SCIP&#39;s main datastructure
SCIP_RETCODE SCIPincludeHeurOneopt(SCIP *scip)
Definition: heur_oneopt.c:893
common defines and data types used in all packages of SCIP