# SCIP

Solving Constraint Integer Programs

heur_dualval.h
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1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
5 /* */
7 /* fuer Informationstechnik Berlin */
8 /* */
10 /* */
12 /* along with SCIP; see the file COPYING. If not visit scipopt.org. */
13 /* */
14 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
15
16 /**@file heur_dualval.h
17  * @ingroup PRIMALHEURISTICS
18  * @brief primal heuristic that uses dualvalues for successive switching variable values
19  * @author Tobias Buchwald
20  *
21  * This heuristic tries to find solutions by taking the LP or NLP, rounding solution values, fixing the variables to the
22  * rounded values and then changing some of the values.To determine which variable is changed we give each variable a
23  * ranking dependent on its dualvalue. We work with a transformed problem that is always feasible and has objective = 0
24  * iff the original problem is also feasible. Thus we cannot expect to find really good solutions.
25  */
26
27 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
28
29 #ifndef __SCIP_HEUR_DUALVAL_H__
30 #define __SCIP_HEUR_DUALVAL_H__
31
32 #include "scip/def.h"
33 #include "scip/type_heur.h"
34 #include "scip/type_result.h"
35 #include "scip/type_retcode.h"
36 #include "scip/type_scip.h"
37 #include "scip/type_sol.h"
38
39 #ifdef __cplusplus
40 extern "C" {
41 #endif
42
43 /** creates the dualVal primal heuristic and includes it in SCIP
44  *
45  * @ingroup PrimalHeuristicIncludes
46  */
47 SCIP_EXPORT
49  SCIP* scip /**< SCIP data structure */
50  );
51
53  *
54  * @{
55  */
56
57 /** main procedure of the dualval heuristic */
58 SCIP_EXPORT
60  SCIP* scip, /**< original SCIP data structure */
61  SCIP_HEUR* heur, /**< heuristic data structure */
62  SCIP_RESULT* result, /**< pointer to store result of: did not run, solution found, no solution
63  * found, or fixing is infeasible (cutoff) */
64  SCIP_SOL* refpoint /**< point to take fixation of discrete variables from; if NULL, then LP
65  * solution is used */
66  );
67
68 /** @} */
69
70 #ifdef __cplusplus
71 }
72 #endif
73
74 #endif
enum SCIP_Result SCIP_RESULT
Definition: type_result.h:52
SCIP_RETCODE SCIPapplyHeurDualval(SCIP *scip, SCIP_HEUR *heur, SCIP_RESULT *result, SCIP_SOL *refpoint)
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:54
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