event_estim.h

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/**@file   event_estim.h
 * @ingroup EVENTS
 * @brief  event handler for tree size estimation and restarts
 *
 * This event handler plugin provides different methods for approximating the current fraction of the search
 * that has already been completed and for estimating the total tree size at completion.
 * It can trigger restarts of the current run if the current run seems hopeless.
 *
 * For details about the available approximations of search completion, please see
 *
 * Anderson, Hendel, Le Bodic, Pfetsch
 * Estimating The Size of Branch-and-Bound Trees
 * under preparation
 *
 * This code is a largely enriched version of a code that was used for clairvoyant restarts, see
 *
 * Anderson, Hendel, Le Bodic, Viernickel
 * Clairvoyant Restarts in Branch-and-Bound Search Using Online Tree-Size Estimation
 * AAAI-19: Proceedings of the Thirty-Third AAAI Conference on Artificial Intelligence, 2018
 *
 * @author Gregor Hendel
 */

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

#ifndef __SCIP_EVENT_ESTIM_H__
#define __SCIP_EVENT_ESTIM_H__


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

#ifdef __cplusplus
extern "C" {
#endif

/** creates event handler for tree size estimation */
SCIP_EXPORT
SCIP_RETCODE SCIPincludeEventHdlrEstim(
   SCIP*                 scip                /**< SCIP data structure */
   );

/* return an estimation of the final tree size */
SCIP_EXPORT
SCIP_Real SCIPgetTreesizeEstimation(
   SCIP*                 scip                /**< SCIP data structure */
   );

#ifdef __cplusplus
}
#endif

#endif