Scippy

GCG

Branch-and-Price & Column Generation for Everyone

heur_masterfracdiving.h
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1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the program */
4 /* GCG --- Generic Column Generation */
5 /* a Dantzig-Wolfe decomposition based extension */
6 /* of the branch-cut-and-price framework */
7 /* SCIP --- Solving Constraint Integer Programs */
8 /* */
9 /* Copyright (C) 2010-2021 Operations Research, RWTH Aachen University */
10 /* Zuse Institute Berlin (ZIB) */
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27 
28 /**@file heur_masterfracdiving.h
29  * @ingroup DIVINGHEURISTICS
30  * @brief master LP diving heuristic that chooses fixings w.r.t. the fractionalities
31  * @author Tobias Achterberg
32  *
33  * Diving heuristic: Iteratively fixes some fractional variable and resolves the LP-relaxation, thereby simulating a
34  * depth-first-search in the tree. Fractional Diving chooses the variable with the highest fractionality and rounds it to the
35  * nearest integer. One-level backtracking is applied: If the LP gets infeasible, the last fixing is undone, and the
36  * opposite fixing is tried. If this is infeasible, too, the procedure aborts.
37  */
38 
39 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
40 
41 #ifndef __SCIP_HEUR_MASTERFRACDIVING_H__
42 #define __SCIP_HEUR_MASTERFRACDIVING_H__
43 
44 
45 #include "scip/scip.h"
46 
47 #ifdef __cplusplus
48 extern "C" {
49 #endif
50 
51 /** creates the masterfracdiving heuristic and includes it in GCG */
52 SCIP_EXPORT
54  SCIP* scip /**< SCIP data structure */
55  );
56 
57 #ifdef __cplusplus
58 }
59 #endif
60 
61 #endif
SCIP_EXPORT SCIP_RETCODE GCGincludeHeurMasterfracdiving(SCIP *scip)