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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* */
/* This file is part of the program and library */
/* SCIP --- Solving Constraint Integer Programs */
/* */
/* Copyright 2002-2022 Zuse Institute Berlin */
/* */
/* Licensed under the Apache License, Version 2.0 (the "License"); */
/* you may not use this file except in compliance with the License. */
/* You may obtain a copy of the License at */
/* */
/* http://www.apache.org/licenses/LICENSE-2.0 */
/* */
/* Unless required by applicable law or agreed to in writing, software */
/* distributed under the License is distributed on an "AS IS" BASIS, */
/* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */
/* See the License for the specific language governing permissions and */
/* limitations under the License. */
/* */
/* You should have received a copy of the Apache-2.0 license */
/* along with SCIP; see the file LICENSE. If not visit scipopt.org. */
/* */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/**@file branch_pscost.h
* @ingroup BRANCHINGRULES
* @brief pseudo costs branching rule
* @author Tobias Achterberg
*
* The pseudo costs branching rule selects the branching variable with respect to the so-called pseudo costs
* of the variables. Pseudo costs measure the average gain per unit in the objective function when the variable
* was branched on upwards or downwards, resp. The required information is updated at every node of
* the solving process.
*
* The selected variable maximizes the expected gain of the dual bound in the created subtree.
*
* For a more mathematical description and a comparison between the pseudo costs branching rule
* and other branching rules in SCIP, we refer to
*
* @par
* Tobias Achterberg@n
* Constraint Integer Programming@n
* PhD Thesis, Technische Universität Berlin, 2007@n
*/
/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
#ifndef __SCIP_BRANCH_PSCOST_H__
#define __SCIP_BRANCH_PSCOST_H__
#include "scip/def.h"
#include "scip/type_retcode.h"
#include "scip/type_scip.h"
#include "scip/type_var.h"
#ifdef __cplusplus
extern "C" {
#endif
/** creates the pseudo cost branching rule and includes it in SCIP
*
* @ingroup BranchingRuleIncludes
*/
SCIP_EXPORT
SCIP_RETCODE SCIPincludeBranchrulePscost(
SCIP* scip /**< SCIP data structure */
);
/**@addtogroup BRANCHINGRULES
*
* @{
*/
/** selects a branching variable, due to pseudo cost, from the given candidate array and returns this variable together
* with a branching point */
SCIP_EXPORT
SCIP_RETCODE SCIPselectBranchVarPscost(
SCIP* scip, /**< SCIP data structure */
SCIP_VAR** branchcands, /**< branching candidates */
SCIP_Real* branchcandssol, /**< solution value for the branching candidates */
SCIP_Real* branchcandsscore, /**< array of candidate scores */
int nbranchcands, /**< number of branching candidates */
SCIP_VAR** var, /**< pointer to store the variable to branch on, or NULL if none */
SCIP_Real* brpoint /**< pointer to store the branching point for the branching variable, will be fractional for a discrete variable */
);
/** @} */
#ifdef __cplusplus
}
#endif
#endif