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4    	/*         SCIP --- Solving Constraint Integer Programs                      */
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24   	
25   	/**@file   branch_fullstrong.h
26   	 * @ingroup BRANCHINGRULES
27   	 * @brief  full strong LP branching rule
28   	 * @author Tobias Achterberg
29   	 *
30   	 * The full strong branching rule applies strong branching to every fractional variable of the LP solution
31   	 * at the current node of the branch-and-bound search. The rule selects the candidate
32   	 * which will cause the highest gain of the dual bound in the created sub-tree among all branching variables.
33   	 *
34   	 * For calculating the gain, a look-ahead is performed by solving the child node LPs which will result
35   	 * from branching on a variable.
36   	 *
37   	 * For a more mathematical description and a comparison between the strong branching rule and other branching rules
38   	 * in SCIP, we refer to
39   	 *
40   	 * @par
41   	 * Tobias Achterberg@n
42   	 * Constraint Integer Programming@n
43   	 * PhD Thesis, Technische Universität Berlin, 2007@n
44   	 *
45   	 *
46   	 */
47   	
48   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
49   	
50   	#ifndef __SCIP_BRANCH_FULLSTRONG_H__
51   	#define __SCIP_BRANCH_FULLSTRONG_H__
52   	
53   	
54   	#include "scip/def.h"
55   	#include "scip/type_result.h"
56   	#include "scip/type_retcode.h"
57   	#include "scip/type_scip.h"
58   	#include "scip/type_var.h"
59   	
60   	#ifdef __cplusplus
61   	extern "C" {
62   	#endif
63   	
64   	/** creates the full strong LP branching rule and includes it in SCIP
65   	 *
66   	 *  @ingroup BranchingRuleIncludes
67   	 */
68   	SCIP_EXPORT
69   	SCIP_RETCODE SCIPincludeBranchruleFullstrong(
70   	   SCIP*                 scip                /**< SCIP data structure */
71   	   );
72   	
73   	/**@addtogroup BRANCHINGRULES
74   	 *
75   	 * @{
76   	 */
77   	
78   	/**
79   	 * Selects a variable from a set of candidates by strong branching
80   	 *
81   	 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
82   	 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
83   	 *
84   	 * @note The variables in the lpcands array must have a fractional value in the current LP solution
85   	 */
86   	SCIP_EXPORT
87   	SCIP_RETCODE SCIPselectVarStrongBranching(
88   	   SCIP*                 scip,               /**< original SCIP data structure                        */
89   	   SCIP_VAR**            lpcands,            /**< branching candidates                                */
90   	   SCIP_Real*            lpcandssol,         /**< solution values of the branching candidates         */
91   	   SCIP_Real*            lpcandsfrac,        /**< fractional values of the branching candidates       */
92   	   SCIP_Bool*            skipdown,           /**< should down branchings be skipped? */
93   	   SCIP_Bool*            skipup,             /**< should up branchings be skipped? */
94   	   int                   nlpcands,           /**< number of branching candidates                      */
95   	   int                   npriolpcands,       /**< number of priority branching candidates             */
96   	   int                   ncomplete,          /**< number of branching candidates without skip         */
97   	   int*                  start,              /**< starting index in lpcands                           */
98   	   int                   maxproprounds,      /**< maximum number of propagation rounds to be performed during strong
99   	                                              *   branching before solving the LP (-1: no limit, -2: parameter settings) */
100  	   SCIP_Bool             probingbounds,      /**< should valid bounds be identified in a probing-like fashion during
101  	                                              *   strong branching (only with propagation)? */
102  	   SCIP_Bool             forcestrongbranch,  /**< should strong branching be applied even if there is just a single candidate? */
103  	   int*                  bestcand,           /**< best candidate for branching                        */
104  	   SCIP_Real*            bestdown,           /**< objective value of the down branch for bestcand     */
105  	   SCIP_Real*            bestup,             /**< objective value of the up branch for bestcand       */
106  	   SCIP_Real*            bestscore,          /**< score for bestcand                                  */
107  	   SCIP_Bool*            bestdownvalid,      /**< is bestdown a valid dual bound for the down branch? */
108  	   SCIP_Bool*            bestupvalid,        /**< is bestup a valid dual bound for the up branch?     */
109  	   SCIP_Real*            provedbound,        /**< proved dual bound for current subtree               */
110  	   SCIP_RESULT*          result              /**< result pointer                                      */
111  	   );
112  	
113  	/** @} */
114  	
115  	#ifdef __cplusplus
116  	}
117  	#endif
118  	
119  	#endif
120