Scippy

SCIP

Solving Constraint Integer Programs

heur_guideddiving.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 */
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8 /* Licensed under the Apache License, Version 2.0 (the "License"); */
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21 /* along with SCIP; see the file LICENSE. If not visit scipopt.org. */
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23 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24 
25 /**@file heur_guideddiving.h
26  * @ingroup PRIMALHEURISTICS
27  * @brief LP diving heuristic that chooses fixings in direction of incumbent solutions
28  * @author Tobias Achterberg
29  *
30  * Diving heuristic: Iteratively fixes some fractional variable and resolves the LP-relaxation, thereby simulating a
31  * depth-first-search in the tree. Guided Diving chooses the fractional variable which is closest to that variable's
32  * value in the incumbent solution and rounds it to the incumbent's value. One-level backtracking is applied: If the LP
33  * gets infeasible, the last fixing is undone, and the opposite fixing is tried. If this is infeasible, too, the
34  * procedure aborts.
35  */
36 
37 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
38 
39 #ifndef __SCIP_HEUR_GUIDEDDIVING_H__
40 #define __SCIP_HEUR_GUIDEDDIVING_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 guideddiving 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
SCIP_RETCODE SCIPincludeHeurGuideddiving(SCIP *scip)
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
common defines and data types used in all packages of SCIP