heur_zirounding.h

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/*         SCIP --- Solving Constraint Integer Programs                      */
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/*    Copyright (C) 2002-2021 Konrad-Zuse-Zentrum                            */
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/**@file   heur_zirounding.h
 * @ingroup PRIMALHEURISTICS
 * @brief  ZI Round primal heuristic
 * @author Gregor Hendel
 *
 * ZI Round (C. Wallace, Journal of Heuristics 2009) reduces the integer infeasibility of an LP solution step-by-step by
 * shifting fractional values towards integrality, but not necessarily rounding them.  For each integer variable with
 * fractional solution value, the heuristic calculates bounds for both possible rounding directions such that the
 * obtained solution stays LP-feasible. The solution value is then shifted by the corresponding bound into the direction
 * which reduces the fractionality most.
 */

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#ifndef __SCIP_HEUR_ZIROUNDING_H__
#define __SCIP_HEUR_ZIROUNDING_H__

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

#ifdef __cplusplus
extern "C" {
#endif

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

#ifdef __cplusplus
}
#endif

#endif