heur_linesearchdiving.h

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/*                  This file is part of the program and library             */
/*         SCIP --- Solving Constraint Integer Programs                      */
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/*    Copyright (C) 2002-2018 Konrad-Zuse-Zentrum                            */
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/**@file   heur_linesearchdiving.h
 * @ingroup PRIMALHEURISTICS
 * @brief  LP diving heuristic that fixes variables with a large difference to their root solution
 * @author Tobias Achterberg
 *
 * Diving heuristic: Iteratively fixes some fractional variable and resolves the LP-relaxation, thereby simulating a
 * depth-first-search in the tree. Line search diving chooses the variable with the greatest difference of its root LP
 * solution and the current LP solution, hence, the variable that developed most.  It is fixed to the next integer in
 * the direction it developed. One-level backtracking is applied: If the LP gets infeasible, the last fixing is undone,
 * and the opposite fixing is tried. If this is infeasible, too, the procedure aborts.
 */

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#ifndef __SCIP_HEUR_LINESEARCHDIVING_H__
#define __SCIP_HEUR_LINESEARCHDIVING_H__

#include "scip/def.h"
#include "scip/type_retcode.h"
#include "scip/type_scip.h"

#ifdef __cplusplus
extern "C" {
#endif

/** creates the linesearchdiving primal heuristic and includes it in SCIP
 *
 *  @ingroup PrimalHeuristicIncludes
 */
extern
SCIP_RETCODE SCIPincludeHeurLinesearchdiving(
   SCIP*                 scip                /**< SCIP data structure */
   );

#ifdef __cplusplus
}
#endif

#endif