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 /* */
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24 
25 /**@file branch_allfullstrong.h
26  * @ingroup BRANCHINGRULES
27  * @brief all variables full strong LP branching rule
28  * @author Tobias Achterberg
29  * @author Gerald Gamrath
30  *
31  * The all variables full strong branching rule applies strong branching to every non-fixed variable
32  * at the current node of the branch-and-bound search. The rule selects the candidate
33  * which will cause the highest gain of the dual bound in the created sub-tree among all branching variables.
34  *
35  * For calculating the gain, a look-ahead is performed by solving the child node LPs which will result
36  * from branching on a variable.
37  *
38  * For a more mathematical description and a comparison between the strong branching rule and other branching rules
39  * in SCIP, we refer to
40  *
41  * @par
42  * Tobias Achterberg@n
43  * Constraint Integer Programming@n
44  * PhD Thesis, Technische Universit├Ąt Berlin, 2007@n
45  *
46 
47  */
48 
49 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
50 
51 #ifndef __SCIP_BRANCH_ALLFULLSTRONG_H__
52 #define __SCIP_BRANCH_ALLFULLSTRONG_H__
53 
54 
55 #include "scip/def.h"
56 #include "scip/type_result.h"
57 #include "scip/type_retcode.h"
58 #include "scip/type_scip.h"
59 #include "scip/type_var.h"
60 
61 #ifdef __cplusplus
62 extern "C" {
63 #endif
64 
65 
66 /**
67  * Selects a variable from a set of candidates by strong branching
68  *
69  * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
70  * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
71  *
72  * @note The variables in the lpcands array must have a fractional value in the current LP solution
73  */
74 SCIP_EXPORT
76  SCIP* scip, /**< original SCIP data structure */
77  SCIP_VAR** pseudocands, /**< branching candidates */
78  SCIP_Bool* skipdown, /**< should down branchings be skipped? */
79  SCIP_Bool* skipup, /**< should up branchings be skipped? */
80  int npseudocands, /**< number of branching candidates */
81  int npriopseudocands, /**< number of priority branching candidates */
82  int* bestpseudocand, /**< best candidate for branching */
83  SCIP_Real* bestdown, /**< objective value of the down branch for bestcand */
84  SCIP_Real* bestup, /**< objective value of the up branch for bestcand */
85  SCIP_Real* bestscore, /**< score for bestcand */
86  SCIP_Bool* bestdownvalid, /**< is bestdown a valid dual bound for the down branch? */
87  SCIP_Bool* bestupvalid, /**< is bestup a valid dual bound for the up branch? */
88  SCIP_Real* provedbound, /**< proved dual bound for current subtree */
89  SCIP_RESULT* result /**< result pointer */
90  );
91 
92 /** creates the all variables full strong LP branching rule and includes it in SCIP */
93 SCIP_EXPORT
95  SCIP* scip /**< SCIP data structure */
96  );
97 
98 #ifdef __cplusplus
99 }
100 #endif
101 
102 #endif
enum SCIP_Result SCIP_RESULT
Definition: type_result.h:61
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
type definitions for problem variables
SCIP_RETCODE SCIPincludeBranchruleAllfullstrong(SCIP *scip)
#define SCIP_Bool
Definition: def.h:91
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)
#define SCIP_Real
Definition: def.h:173
result codes for SCIP callback methods
common defines and data types used in all packages of SCIP