event_estim.h

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*                                                                           */
/*                  This file is part of the program and library             */
/*         SCIP --- Solving Constraint Integer Programs                      */
/*                                                                           */
/*    Copyright (C) 2002-2020 Konrad-Zuse-Zentrum                            */
/*                            fuer Informationstechnik Berlin                */
/*                                                                           */
/*  SCIP is distributed under the terms of the ZIB Academic License.         */
/*                                                                           */
/*  You should have received a copy of the ZIB Academic License              */
/*  along with SCIP; see the file COPYING. If not visit scipopt.org.         */
/*                                                                           */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/**@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/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