heur_guideddiving.h

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/**@file   heur_guideddiving.h
 * @ingroup PRIMALHEURISTICS
 * @brief  LP diving heuristic that chooses fixings in direction of incumbent solutions
 * @author Tobias Achterberg
 *
 * Diving heuristic: Iteratively fixes some fractional variable and resolves the LP-relaxation, thereby simulating a
 * depth-first-search in the tree. Guided Diving chooses the fractional variable which is closest to that variable's
 * value in the incumbent solution and rounds it to the incumbent's value.  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_GUIDEDDIVING_H__
#define __SCIP_HEUR_GUIDEDDIVING_H__

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

#ifdef __cplusplus
extern "C" {
#endif

/** creates the guideddiving heuristic and includes it in SCIP
 *
 *  @ingroup PrimalHeuristicIncludes
 */
SCIP_EXPORT
SCIP_RETCODE SCIPincludeHeurGuideddiving(
   SCIP*                 scip                /**< SCIP data structure */
   );

#ifdef __cplusplus
}
#endif

#endif