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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 Universität 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
66   	SCIP_RETCODE SCIPincludeBranchrulePscost(
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
78   	SCIP_RETCODE SCIPselectBranchVarPscost(
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
95