Scippy

SCIP

Solving Constraint Integer Programs

branch_pscost.h
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2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
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24 
25 /**@file branch_pscost.h
26  * @ingroup BRANCHINGRULES
27  * @brief pseudo costs branching rule
28  * @author Tobias Achterberg
29  *
30  * The pseudo costs branching rule selects the branching variable with respect to the so-called pseudo costs
31  * of the variables. Pseudo costs measure the average gain per unit in the objective function when the variable
32  * was branched on upwards or downwards, resp. The required information is updated at every node of
33  * the solving process.
34  *
35  * The selected variable maximizes the expected gain of the dual bound in the created subtree.
36  *
37  * For a more mathematical description and a comparison between the pseudo costs branching rule
38  * and other branching rules in SCIP, we refer to
39  *
40  * @par
41  * Tobias Achterberg@n
42  * Constraint Integer Programming@n
43  * PhD Thesis, Technische Universit├Ąt Berlin, 2007@n
44  */
45 
46 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
47 
48 #ifndef __SCIP_BRANCH_PSCOST_H__
49 #define __SCIP_BRANCH_PSCOST_H__
50 
51 
52 #include "scip/def.h"
53 #include "scip/type_retcode.h"
54 #include "scip/type_scip.h"
55 #include "scip/type_var.h"
56 
57 #ifdef __cplusplus
58 extern "C" {
59 #endif
60 
61 /** creates the pseudo cost branching rule and includes it in SCIP
62  *
63  * @ingroup BranchingRuleIncludes
64  */
65 SCIP_EXPORT
67  SCIP* scip /**< SCIP data structure */
68  );
69 
70 /**@addtogroup BRANCHINGRULES
71  *
72  * @{
73  */
74 
75 /** selects a branching variable, due to pseudo cost, from the given candidate array and returns this variable together
76  * with a branching point */
77 SCIP_EXPORT
79  SCIP* scip, /**< SCIP data structure */
80  SCIP_VAR** branchcands, /**< branching candidates */
81  SCIP_Real* branchcandssol, /**< solution value for the branching candidates */
82  SCIP_Real* branchcandsscore, /**< array of candidate scores */
83  int nbranchcands, /**< number of branching candidates */
84  SCIP_VAR** var, /**< pointer to store the variable to branch on, or NULL if none */
85  SCIP_Real* brpoint /**< pointer to store the branching point for the branching variable, will be fractional for a discrete variable */
86  );
87 
88 /** @} */
89 
90 #ifdef __cplusplus
91 }
92 #endif
93 
94 #endif
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
type definitions for return codes for SCIP methods
SCIP_RETCODE SCIPselectBranchVarPscost(SCIP *scip, SCIP_VAR **branchcands, SCIP_Real *branchcandssol, SCIP_Real *branchcandsscore, int nbranchcands, SCIP_VAR **var, SCIP_Real *brpoint)
type definitions for SCIP&#39;s main datastructure
type definitions for problem variables
#define SCIP_Real
Definition: def.h:173
SCIP_RETCODE SCIPincludeBranchrulePscost(SCIP *scip)
common defines and data types used in all packages of SCIP