Scippy

SCIP

Solving Constraint Integer Programs

branch_allfullstrong.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) 2002-2021 Konrad-Zuse-Zentrum */
7 /* fuer Informationstechnik Berlin */
8 /* */
9 /* SCIP is distributed under the terms of the ZIB Academic License. */
10 /* */
11 /* You should have received a copy of the ZIB Academic License */
12 /* along with SCIP; see the file COPYING. If not visit scipopt.org. */
13 /* */
14 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
15 
16 /**@file branch_allfullstrong.h
17  * @ingroup BRANCHINGRULES
18  * @brief all variables full strong LP branching rule
19  * @author Tobias Achterberg
20  * @author Gerald Gamrath
21  *
22  * The all variables full strong branching rule applies strong branching to every non-fixed variable
23  * at the current node of the branch-and-bound search. The rule selects the candidate
24  * which will cause the highest gain of the dual bound in the created sub-tree among all branching variables.
25  *
26  * For calculating the gain, a look-ahead is performed by solving the child node LPs which will result
27  * from branching on a variable.
28  *
29  * For a more mathematical description and a comparison between the strong branching rule and other branching rules
30  * in SCIP, we refer to
31  *
32  * @par
33  * Tobias Achterberg@n
34  * Constraint Integer Programming@n
35  * PhD Thesis, Technische Universit├Ąt Berlin, 2007@n
36  *
37 
38  */
39 
40 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
41 
42 #ifndef __SCIP_BRANCH_ALLFULLSTRONG_H__
43 #define __SCIP_BRANCH_ALLFULLSTRONG_H__
44 
45 
46 #include "scip/def.h"
47 #include "scip/type_result.h"
48 #include "scip/type_retcode.h"
49 #include "scip/type_scip.h"
50 #include "scip/type_var.h"
51 
52 #ifdef __cplusplus
53 extern "C" {
54 #endif
55 
56 
57 /**
58  * Selects a variable from a set of candidates by strong branching
59  *
60  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
61  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
62  *
63  * @note The variables in the lpcands array must have a fractional value in the current LP solution
64  */
67  SCIP* scip, /**< original SCIP data structure */
68  SCIP_VAR** pseudocands, /**< branching candidates */
69  SCIP_Bool* skipdown, /**< should down branchings be skipped? */
70  SCIP_Bool* skipup, /**< should up branchings be skipped? */
71  int npseudocands, /**< number of branching candidates */
72  int npriopseudocands, /**< number of priority branching candidates */
73  int* bestpseudocand, /**< best candidate for branching */
74  SCIP_Real* bestdown, /**< objective value of the down branch for bestcand */
75  SCIP_Real* bestup, /**< objective value of the up branch for bestcand */
76  SCIP_Real* bestscore, /**< score for bestcand */
77  SCIP_Bool* bestdownvalid, /**< is bestdown a valid dual bound for the down branch? */
78  SCIP_Bool* bestupvalid, /**< is bestup a valid dual bound for the up branch? */
79  SCIP_Real* provedbound, /**< proved dual bound for current subtree */
80  SCIP_RESULT* result /**< result pointer */
81  );
82 
83 /** creates the all variables full strong LP branching rule and includes it in SCIP */
86  SCIP* scip /**< SCIP data structure */
87  );
88 
89 #ifdef __cplusplus
90 }
91 #endif
92 
93 #endif
enum SCIP_Result SCIP_RESULT
Definition: type_result.h:52
#define SCIP_EXPORT
Definition: def.h:100
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:54
type definitions for return codes for SCIP methods
type definitions for SCIP&#39;s main datastructure
type definitions for problem variables
#define SCIP_Bool
Definition: def.h:70
SCIP_EXPORT SCIP_RETCODE SCIPselectVarPseudoStrongBranching(SCIP *scip, SCIP_VAR **pseudocands, SCIP_Bool *skipdown, SCIP_Bool *skipup, int npseudocands, int npriopseudocands, int *bestpseudocand, SCIP_Real *bestdown, SCIP_Real *bestup, SCIP_Real *bestscore, SCIP_Bool *bestdownvalid, SCIP_Bool *bestupvalid, SCIP_Real *provedbound, SCIP_RESULT *result)
SCIP_EXPORT SCIP_RETCODE SCIPincludeBranchruleAllfullstrong(SCIP *scip)
#define SCIP_Real
Definition: def.h:163
result codes for SCIP callback methods
common defines and data types used in all packages of SCIP