heur_nlpdiving.h

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/**@file   heur_nlpdiving.h
 * @ingroup PRIMALHEURISTICS
 * @brief  NLP diving heuristic that chooses fixings w.r.t. the fractionalities
 * @author Timo Berthold
 * @author Stefan Vigerske
 *
 * Diving heuristic: Iteratively fixes some fractional variables and resolves the LP and NLP relaxations, thereby simulating a
 * depth-first-search in the tree. Double Diving chooses the variable for which the sum of the distances from the relaxations'
 * solutions to a common integer value is minimal and rounds it to thenearest integer.
 * One-level backtracking is applied: If the NLP gets infeasible, the last fixing 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_NLPDIVING_H__
#define __SCIP_HEUR_NLPDIVING_H__
 
#include "scip/def.h"
#include "scip/type_retcode.h"
#include "scip/type_scip.h"
 
#ifdef __cplusplus
extern "C" {
#endif
 
/** creates the fracdiving heuristic and includes it in SCIP
 *
 *  @ingroup PrimalHeuristicIncludes
 */
SCIP_EXPORT
SCIP_RETCODE SCIPincludeHeurNlpdiving(
   SCIP*                 scip                /**< SCIP data structure */
   );
 
#ifdef __cplusplus
}
#endif
 
#endif