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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 Universität 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
75   	SCIP_RETCODE SCIPselectVarPseudoStrongBranching(
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
94   	SCIP_RETCODE SCIPincludeBranchruleAllfullstrong(
95   	   SCIP*                 scip                /**< SCIP data structure */
96   	   );
97   	
98   	#ifdef __cplusplus
99   	}
100  	#endif
101  	
102  	#endif
103