Scippy

SCIP

Solving Constraint Integer Programs

heur_nlpdiving.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 (c) 2002-2023 Zuse Institute Berlin (ZIB) */
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 /* */
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21 /* along with SCIP; see the file LICENSE. If not visit scipopt.org. */
22 /* */
23 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24 
25 /**@file heur_nlpdiving.h
26  * @ingroup PRIMALHEURISTICS
27  * @brief NLP diving heuristic that chooses fixings w.r.t. the fractionalities
28  * @author Timo Berthold
29  * @author Stefan Vigerske
30  *
31  * Diving heuristic: Iteratively fixes some fractional variables and resolves the LP and NLP relaxations, thereby simulating a
32  * depth-first-search in the tree. Double Diving chooses the variable for which the sum of the distances from the relaxations'
33  * solutions to a common integer value is minimal and rounds it to thenearest integer.
34  * One-level backtracking is applied: If the NLP gets infeasible, the last fixing is undone, and the opposite fixing is tried.
35  * If this is infeasible, too, the procedure aborts.
36  */
37 
38 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
39 
40 #ifndef __SCIP_HEUR_NLPDIVING_H__
41 #define __SCIP_HEUR_NLPDIVING_H__
42 
43 #include "scip/def.h"
44 #include "scip/type_retcode.h"
45 #include "scip/type_scip.h"
46 
47 #ifdef __cplusplus
48 extern "C" {
49 #endif
50 
51 /** creates the fracdiving heuristic and includes it in SCIP
52  *
53  * @ingroup PrimalHeuristicIncludes
54  */
55 SCIP_EXPORT
57  SCIP* scip /**< SCIP data structure */
58  );
59 
60 #ifdef __cplusplus
61 }
62 #endif
63 
64 #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 SCIPincludeHeurNlpdiving(SCIP *scip)
common defines and data types used in all packages of SCIP