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4    	/*         SCIP --- Solving Constraint Integer Programs                      */
5    	/*                                                                           */
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24   	
25   	/**@file   heur_farkasdiving.h
26   	 * @ingroup PRIMALHEURISTICS
27   	 * @brief  LP diving heuristic that tries to construct a Farkas-proof
28   	 * @author Jakob Witzig
29   	 *
30   	 * The heuristic dives into the direction of the pseudosolution, i.e., variables get rounded
31   	 * towards their best bound w.r.t there objective coefficient. This strategy is twofold, if
32   	 * a feasible solution is found the solution has potentially a very good objective value; on the other
33   	 * hand, the left-hand side of a potential Farkas-proof \f$y^Tb - y^TA{l',u'} > 0\f$ (i.e., infeasibility proof)
34   	 * gets increased, where \f$l',u'\f$ are the local bounds. The contribution of each variable \f$x_i\f$ to the
35   	 * Farkas-proof can be approximated by \f$c_i = y^TA_i\f$ because we only dive on basic variables with
36   	 * reduced costs \f$c_i - y^TA_i = 0\f$.
37   	 */
38   	
39   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
40   	
41   	#ifndef __SCIP_HEUR_FARKASDIVING_H__
42   	#define __SCIP_HEUR_FARKASDIVING_H__
43   	
44   	#include "scip/def.h"
45   	#include "scip/type_retcode.h"
46   	#include "scip/type_scip.h"
47   	
48   	#ifdef __cplusplus
49   	extern "C" {
50   	#endif
51   	
52   	/** creates the farkasdiving heuristic and includes it in SCIP
53   	 *
54   	 *  @ingroup PrimalHeuristicIncludes
55   	 */
56   	SCIP_EXPORT
57   	SCIP_RETCODE SCIPincludeHeurFarkasdiving(
58   	   SCIP*                 scip                /**< SCIP data structure */
59   	   );
60   	
61   	#ifdef __cplusplus
62   	}
63   	#endif
64   	
65   	#endif
66