heur_indicatordiving.h

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/**@file   heur_indicatordiving.h
 * @ingroup PRIMALHEURISTICS
 * @brief  LP diving heuristic that fixes indicator variables controlling semicontinuous variables
 * @author Katrin Halbig
 * @author Alexander Hoen
 *
 * A diving heuristic iteratively rounds some fractional variables or variables determined by constraint handlers,
 * and resolves the LP relaxation. Thereby simulating a depth-first-search in the tree.
 *
 * Indicatordiving focuses on indicator variables, which control semicontinuous variables.
 * If the semicontinuous variable is unbounded, the indicator constraint is not part of the LP and,
 * therefore, the indicator variable is not set to an useful value in the LP solution.
 *
 * For these indicator variables the score depends on the LP value and the bounds of the corresponding semicontinuous variable.
 * If parameter usevarbounds=TRUE, also varbound constraints modeling semicontinuous variables are considered.
 * For all other variables the Farkas score (scaled) is returned.
 */

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#ifndef __SCIP_HEUR_INDICATORDIVING_H__
#define __SCIP_HEUR_INDICATORDIVING_H__

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

#ifdef __cplusplus
extern "C" {
#endif

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

#ifdef __cplusplus
}
#endif

#endif