heur_randrounding.h

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/**@file   heur_randrounding.h
 * @ingroup PRIMALHEURISTICS
 * @brief  randomized LP rounding heuristic which also generates conflicts via an auxiliary probing tree
 * @author Gregor Hendel
 *
 * Randomized LP rounding uses a random variable from a uniform distribution
 * over [0,1] to determine whether the fractional LP value x should be rounded
 * up with probability x - floor(x) or down with probability ceil(x) - x.
 *
 * This implementation uses domain propagation techniques to tighten the variable domains after every
 * rounding step.
 *
 * @see: The most relevant publication is Raghavan & Thompson,
 *       "Randomized rounding: A technique for provably good algorithms and algorithmic proofs",
 *        Combinatorica 7 (4): 365–374
 *        1987
 */
 
/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
 
#ifndef __SCIP_HEUR_RANDROUNDING_H__
#define __SCIP_HEUR_RANDROUNDING_H__
 
#include "scip/def.h"
#include "scip/type_retcode.h"
#include "scip/type_scip.h"
 
#ifdef __cplusplus
extern "C" {
#endif
 
/** creates the rand rounding heuristic and includes it in SCIP
 *
 *  @ingroup PrimalHeuristicIncludes
 */
SCIP_EXPORT
SCIP_RETCODE SCIPincludeHeurRandrounding(
   SCIP*                 scip                /**< SCIP data structure */
   );
 
#ifdef __cplusplus
}
#endif
 
#endif