scip_probing.h

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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*                                                                           */
/*                  This file is part of the program and library             */
/*         SCIP --- Solving Constraint Integer Programs                      */
/*                                                                           */
/*    Copyright (C) 2002-2019 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 scip.zib.de.         */
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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/**@file   scip_probing.h
 * @ingroup PUBLICCOREAPI
 * @brief  public methods for the probing mode
 * @author Tobias Achterberg
 * @author Timo Berthold
 * @author Thorsten Koch
 * @author Alexander Martin
 * @author Marc Pfetsch
 * @author Kati Wolter
 * @author Gregor Hendel
 * @author Robert Lion Gottwald
 */

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

#ifndef __SCIP_SCIP_PROBING_H__
#define __SCIP_SCIP_PROBING_H__


#include "lpi/type_lpi.h"
#include "scip/def.h"
#include "scip/type_heur.h"
#include "scip/type_history.h"
#include "scip/type_lp.h"
#include "scip/type_retcode.h"
#include "scip/type_scip.h"
#include "scip/type_sol.h"
#include "scip/type_var.h"

/* In debug mode, we include the SCIP's structure in scip.c, such that no one can access
 * this structure except the interface methods in scip.c.
 * In optimized mode, the structure is included in scip.h, because some of the methods
 * are implemented as defines for performance reasons (e.g. the numerical comparisons).
 * Additionally, the internal "set.h" is included, such that the defines in set.h are
 * available in optimized mode.
 */
#ifdef NDEBUG
#include "scip/struct_scip.h"
#include "scip/struct_stat.h"
#include "scip/set.h"
#include "scip/tree.h"
#include "scip/misc.h"
#include "scip/var.h"
#include "scip/cons.h"
#include "scip/solve.h"
#include "scip/debug.h"
#endif

#ifdef __cplusplus
extern "C" {
#endif

/**@addtogroup PublicProbingMethods
 *
 * @{
 */

/** returns whether we are in probing mode; probing mode is activated via SCIPstartProbing() and stopped
 *  via SCIPendProbing()
 *
 *  @return TRUE, if SCIP is currently in probing mode, otherwise FALSE
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_TRANSFORMED
 *       - \ref SCIP_STAGE_INITPRESOLVE
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_EXITPRESOLVE
 *       - \ref SCIP_STAGE_PRESOLVED
 *       - \ref SCIP_STAGE_INITSOLVE
 *       - \ref SCIP_STAGE_SOLVING
 *       - \ref SCIP_STAGE_SOLVED
 *       - \ref SCIP_STAGE_EXITSOLVE
 */
extern
SCIP_Bool SCIPinProbing(
   SCIP*                 scip                /**< SCIP data structure */
   );

/** initiates probing, making methods SCIPnewProbingNode(), SCIPbacktrackProbing(), SCIPchgVarLbProbing(),
 *  SCIPchgVarUbProbing(), SCIPfixVarProbing(), SCIPpropagateProbing(), and SCIPsolveProbingLP() available
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 *
 *  @note The collection of variable statistics is turned off during probing. If these statistics should be collected
 *        during probing use the method SCIPenableVarHistory() to turn the collection explicitly on.
 */
extern
SCIP_RETCODE SCIPstartProbing(
   SCIP*                 scip                /**< SCIP data structure */
   );

/** creates a new probing sub node, whose changes can be undone by backtracking to a higher node in the probing path
 *  with a call to SCIPbacktrackProbing();
 *  using a sub node for each set of probing bound changes can improve conflict analysis
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPnewProbingNode(
   SCIP*                 scip                /**< SCIP data structure */
   );

/** returns the current probing depth
 *
 *  @return the probing depth, i.e. the number of probing sub nodes existing in the probing path
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
int SCIPgetProbingDepth(
   SCIP*                 scip                /**< SCIP data structure */
   );

/** undoes all changes to the problem applied in probing up to the given probing depth;
 *  the changes of the probing node of the given probing depth are the last ones that remain active;
 *  changes that were applied before calling SCIPnewProbingNode() cannot be undone
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPbacktrackProbing(
   SCIP*                 scip,               /**< SCIP data structure */
   int                   probingdepth        /**< probing depth of the node in the probing path that should be reactivated */
   );

/** quits probing and resets bounds and constraints to the focus node's environment
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPendProbing(
   SCIP*                 scip                /**< SCIP data structure */
   );

/** injects a change of variable's lower bound into current probing node; the same can also be achieved with a call to
 *  SCIPchgVarLb(), but in this case, the bound change would be treated like a deduction instead of a branching decision
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPchgVarLbProbing(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_VAR*             var,                /**< variable to change the bound for */
   SCIP_Real             newbound            /**< new value for bound */
   );

/** injects a change of variable's upper bound into current probing node; the same can also be achieved with a call to
 *  SCIPchgVarUb(), but in this case, the bound change would be treated like a deduction instead of a branching decision
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPchgVarUbProbing(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_VAR*             var,                /**< variable to change the bound for */
   SCIP_Real             newbound            /**< new value for bound */
   );

/** gets variable's objective value in current probing
 *
 *  @return the variable's objective value in current probing.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_SOLVING
 *
 *  See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
 */
extern
SCIP_Real SCIPgetVarObjProbing(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_VAR*             var                 /**< variable to get the bound for */
   );

/** injects a change of variable's bounds into current probing node to fix the variable to the specified value;
 *  the same can also be achieved with a call to SCIPfixVar(), but in this case, the bound changes would be treated
 *  like deductions instead of branching decisions
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPfixVarProbing(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_VAR*             var,                /**< variable to change the bound for */
   SCIP_Real             fixedval            /**< value to fix variable to */
   );

/** changes (column) variable's objective value during probing mode
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 *
 *  @pre The variable needs to be a column variable.
 */
extern
SCIP_RETCODE SCIPchgVarObjProbing(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_VAR*             var,                /**< variable to change the objective for */
   SCIP_Real             newobj              /**< new objective function value */
   );

/** returns whether the objective function has changed during probing mode
 *
 *  @return \ref TRUE if objective has changed, \ref FALSE otherwise
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_TRANSFORMED
 *       - \ref SCIP_STAGE_INITPRESOLVE
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_EXITPRESOLVE
 *       - \ref SCIP_STAGE_PRESOLVED
 *       - \ref SCIP_STAGE_INITSOLVE
 *       - \ref SCIP_STAGE_SOLVING
 *       - \ref SCIP_STAGE_SOLVED
 *       - \ref SCIP_STAGE_EXITSOLVE
 */
extern
SCIP_Bool SCIPisObjChangedProbing(
   SCIP*                 scip                /**< SCIP data structure */
   );

/** applies domain propagation on the probing sub problem, that was changed after SCIPstartProbing() was called;
 *  the propagated domains of the variables can be accessed with the usual bound accessing calls SCIPvarGetLbLocal()
 *  and SCIPvarGetUbLocal(); the propagation is only valid locally, i.e. the local bounds as well as the changed
 *  bounds due to SCIPchgVarLbProbing(), SCIPchgVarUbProbing(), and SCIPfixVarProbing() are used for propagation
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPpropagateProbing(
   SCIP*                 scip,               /**< SCIP data structure */
   int                   maxproprounds,      /**< maximal number of propagation rounds (-1: no limit, 0: parameter settings) */
   SCIP_Bool*            cutoff,             /**< pointer to store whether the probing node can be cut off */
   SCIP_Longint*         ndomredsfound       /**< pointer to store the number of domain reductions found, or NULL */
   );

/** applies domain propagation on the probing sub problem, that was changed after SCIPstartProbing() was called;
 *  only propagations of the binary variables fixed at the current probing node that are triggered by the implication
 *  graph and the clique table are applied;
 *  the propagated domains of the variables can be accessed with the usual bound accessing calls SCIPvarGetLbLocal()
 *  and SCIPvarGetUbLocal(); the propagation is only valid locally, i.e. the local bounds as well as the changed
 *  bounds due to SCIPchgVarLbProbing(), SCIPchgVarUbProbing(), and SCIPfixVarProbing() are used for propagation
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPpropagateProbingImplications(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_Bool*            cutoff              /**< pointer to store whether the probing node can be cut off */
   );

/** solves the LP at the current probing node (cannot be applied at preprocessing stage);
 *  no separation or pricing is applied
 *
 *  The LP has to be constructed before (you can use SCIPisLPConstructed() or SCIPconstructLP()).
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPsolveProbingLP(
   SCIP*                 scip,               /**< SCIP data structure */
   int                   itlim,              /**< maximal number of LP iterations to perform, or -1 for no limit */
   SCIP_Bool*            lperror,            /**< pointer to store whether an unresolved LP error occurred */
   SCIP_Bool*            cutoff              /**< pointer to store whether the probing LP was infeasible or the objective
                                              *   limit was reached (or NULL, if not needed) */
   );

/** solves the LP at the current probing node (cannot be applied at preprocessing stage) and applies pricing
 *  until the LP is solved to optimality; no separation is applied
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed . See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPsolveProbingLPWithPricing(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_Bool             pretendroot,        /**< should the pricers be called as if we are at the root node? */
   SCIP_Bool             displayinfo,        /**< should info lines be displayed after each pricing round? */
   int                   maxpricerounds,     /**< maximal number of pricing rounds (-1: no limit);
                                              *   a finite limit means that the LP might not be solved to optimality! */
   SCIP_Bool*            lperror,            /**< pointer to store whether an unresolved LP error occurred */
   SCIP_Bool*            cutoff              /**< pointer to store whether the probing LP was infeasible or the objective
                                              *   limit was reached (or NULL, if not needed) */
   );

/** sets the LP state for the current probing node
 *
 *  @note state and norms are stored at the node and later released by SCIP; therefore, the pointers are set
 *        to NULL by the method
 *
 *  @note the pointers to state and norms must not be NULL; however, they may point to a NULL pointer if the
 *        respective information should not be set
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_PRESOLVING
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPsetProbingLPState(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_LPISTATE**       lpistate,           /**< pointer to LP state information (like basis information) */
   SCIP_LPINORMS**       lpinorms,           /**< pointer to LP pricing norms information */
   SCIP_Bool             primalfeas,         /**< primal feasibility when LP state information was stored */
   SCIP_Bool             dualfeas            /**< dual feasibility when LP state information was stored */
   );

/** adds a row to the LP in the current probing node
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_SOLVING
 *
 *  See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
 */
extern
SCIP_RETCODE SCIPaddRowProbing(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_ROW*             row                 /**< row to be added */
   );

/** applies the cuts in the separation storage to the LP and clears the storage afterwards;
 *  this method can only be applied during probing; the user should resolve the probing LP afterwards
 *  in order to get a new solution
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPapplyCutsProbing(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_Bool*            cutoff              /**< pointer to store whether an empty domain was created */
   );

/** solves relaxation(s) at the current probing node (cannot be applied at preprocessing stage);
 *  no separation or pricing is applied
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_SOLVING
 */
extern
SCIP_RETCODE SCIPsolveProbingRelax(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_Bool*            cutoff              /**< pointer to store whether a relaxation was infeasible or the objective
                                              *   limit was reached (or NULL, if not needed) */
   );

/** stores the candidate score and preferred rounding direction for a candidate variable */
extern
SCIP_RETCODE SCIPgetDivesetScore(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_DIVESET*         diveset,            /**< general diving settings */
   SCIP_DIVETYPE         divetype,           /**< represents different methods for a dive set to explore the next children */
   SCIP_VAR*             divecand,           /**< the candidate for which the branching direction is requested */
   SCIP_Real             divecandsol,        /**< LP solution value of the candidate */
   SCIP_Real             divecandfrac,       /**< fractionality of the candidate */
   SCIP_Real*            candscore,          /**< pointer to store the candidate score */
   SCIP_Bool*            roundup             /**< pointer to store whether preferred direction for diving is upwards */
   );

/** update diveset LP statistics, should be called after every LP solved by this diving heuristic */
extern
void SCIPupdateDivesetLPStats(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_DIVESET*         diveset,            /**< diving settings */
   SCIP_Longint          niterstoadd         /**< additional number of LP iterations to be added */
   );

/** update diveset statistics and global diveset statistics */
extern
void SCIPupdateDivesetStats(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_DIVESET*         diveset,            /**< diveset to be reset */
   int                   nprobingnodes,      /**< the number of probing nodes explored this time */
   int                   nbacktracks,        /**< the number of backtracks during probing this time */
   SCIP_Longint          nsolsfound,         /**< the number of solutions found */
   SCIP_Longint          nbestsolsfound,     /**< the number of best solutions found */
   SCIP_Longint          nconflictsfound,    /**< number of new conflicts found this time */
   SCIP_Bool             leavewassol         /**< was a solution found at the leaf? */
   );

/** enforces a probing/diving solution by suggesting bound changes that maximize the score w.r.t. the current diving settings
 *
 *  the process is guided by the enforcement priorities of the constraint handlers and the scoring mechanism provided by
 *  the dive set.
 *  Constraint handlers may suggest diving bound changes in decreasing order of their enforcement priority, based on the
 *  solution values in the solution @p sol and the current local bounds of the variables. A diving bound change
 *  is a triple (variable,branching direction,value) and is used inside SCIPperformGenericDivingAlgorithm().
 *
 *  After a successful call, SCIP holds two arrays of suggested dive bound changes, one for the preferred child
 *  and one for the alternative.
 *
 *  @see SCIPgetDiveBoundChangeData() for retrieving the dive bound change suggestions.
 *
 *  The method stops after the first constraint handler was successful
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_SOLVING
 *
 *  See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
 */
extern
SCIP_RETCODE SCIPgetDiveBoundChanges(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_DIVESET*         diveset,            /**< diving settings to control scoring */
   SCIP_SOL*             sol,                /**< current solution of diving mode */
   SCIP_Bool*            success,            /**< pointer to store whether constraint handler successfully found a variable */
   SCIP_Bool*            infeasible          /**< pointer to store whether the current node was detected to be infeasible */
   );

/** adds a diving bound change to the diving bound change storage of SCIP together with the information if this is a
 *  bound change for the preferred direction or not
 *
 *  @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref
 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_SOLVING
 *
 *  See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
 */
extern
SCIP_RETCODE SCIPaddDiveBoundChange(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_VAR*             var,                /**< variable to apply the bound change to */
   SCIP_BRANCHDIR        dir,                /**< direction of the bound change */
   SCIP_Real             value,              /**< value to adjust this variable bound to */
   SCIP_Bool             preferred           /**< is this a bound change for the preferred child? */
   );

/** get the dive bound change data for the preferred or the alternative direction
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_SOLVING
 *
 *  See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
 */
extern
void SCIPgetDiveBoundChangeData(
   SCIP*                 scip,               /**< SCIP data structure */
   SCIP_VAR***           variables,          /**< pointer to store variables for the specified direction */
   SCIP_BRANCHDIR**      directions,         /**< pointer to store the branching directions */
   SCIP_Real**           values,             /**< pointer to store bound change values */
   int*                  ndivebdchgs,        /**< pointer to store the number of dive bound changes */
   SCIP_Bool             preferred           /**< should the dive bound changes for the preferred child be output? */
   );

/** clear the dive bound change data structures
 *
 *  @pre This method can be called if @p scip is in one of the following stages:
 *       - \ref SCIP_STAGE_SOLVING
 *
 *  See \ref SCIP_Stage "SCIP_STAGE" for a complete list of all possible solving stages.
 */
extern
void SCIPclearDiveBoundChanges(
   SCIP*                 scip                /**< SCIP data structure */
   );

/**@} */

#ifdef __cplusplus
}
#endif

#endif