Scippy

SCIP

Solving Constraint Integer Programs

heur_dualval.h
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3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
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24 
25 /**@file heur_dualval.h
26  * @ingroup PRIMALHEURISTICS
27  * @brief primal heuristic that uses dualvalues for successive switching variable values
28  * @author Tobias Buchwald
29  *
30  * This heuristic tries to find solutions by taking the LP or NLP, rounding solution values, fixing the variables to the
31  * rounded values and then changing some of the values.To determine which variable is changed we give each variable a
32  * ranking dependent on its dualvalue. We work with a transformed problem that is always feasible and has objective = 0
33  * iff the original problem is also feasible. Thus we cannot expect to find really good solutions.
34  */
35 
36 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
37 
38 #ifndef __SCIP_HEUR_DUALVAL_H__
39 #define __SCIP_HEUR_DUALVAL_H__
40 
41 #include "scip/def.h"
42 #include "scip/type_heur.h"
43 #include "scip/type_result.h"
44 #include "scip/type_retcode.h"
45 #include "scip/type_scip.h"
46 #include "scip/type_sol.h"
47 
48 #ifdef __cplusplus
49 extern "C" {
50 #endif
51 
52 /** creates the dualVal primal heuristic and includes it in SCIP
53  *
54  * @ingroup PrimalHeuristicIncludes
55  */
56 SCIP_EXPORT
58  SCIP* scip /**< SCIP data structure */
59  );
60 
61 /**@addtogroup PRIMALHEURISTICS
62  *
63  * @{
64  */
65 
66 /** main procedure of the dualval heuristic */
67 SCIP_EXPORT
69  SCIP* scip, /**< original SCIP data structure */
70  SCIP_HEUR* heur, /**< heuristic data structure */
71  SCIP_RESULT* result, /**< pointer to store result of: did not run, solution found, no solution
72  * found, or fixing is infeasible (cutoff) */
73  SCIP_SOL* refpoint /**< point to take fixation of discrete variables from; if NULL, then LP
74  * solution is used */
75  );
76 
77 /** @} */
78 
79 #ifdef __cplusplus
80 }
81 #endif
82 
83 #endif
enum SCIP_Result SCIP_RESULT
Definition: type_result.h:61
SCIP_RETCODE SCIPapplyHeurDualval(SCIP *scip, SCIP_HEUR *heur, SCIP_RESULT *result, SCIP_SOL *refpoint)
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
type definitions for return codes for SCIP methods
type definitions for primal heuristics
type definitions for SCIP&#39;s main datastructure
type definitions for storing primal CIP solutions
result codes for SCIP callback methods
SCIP_RETCODE SCIPincludeHeurDualval(SCIP *scip)
common defines and data types used in all packages of SCIP