heur_veclendiving.h

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/**@file   heur_veclendiving.h
 * @ingroup PRIMALHEURISTICS
 * @brief  LP diving heuristic that rounds variables with long column vectors
 * @author Tobias Achterberg
 *
 * Diving heuristic: Iteratively fixes some fractional variable and resolves the LP-relaxation, thereby simulating a
 * depth-first-search in the tree. Vectorlength Diving chooses the variable with the smallest ratio of potential
 * objective change and number of affected constraints and fixes it. One-level backtracking is applied: If the LP gets
 * infeasible, the last fixings is undone, and the opposite fixing is tried. If this is infeasible, too, the procedure
 * aborts.
 */

/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/

#ifndef __SCIP_HEUR_VECLENDIVING_H__
#define __SCIP_HEUR_VECLENDIVING_H__

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

#ifdef __cplusplus
extern "C" {
#endif

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

#ifdef __cplusplus
}
#endif

#endif