1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ 2 /* */ 3 /* This file is part of the program and library */ 4 /* SCIP --- Solving Constraint Integer Programs */ 5 /* */ 6 /* Copyright (c) 2002-2023 Zuse Institute Berlin (ZIB) */ 7 /* */ 8 /* Licensed under the Apache License, Version 2.0 (the "License"); */ 9 /* you may not use this file except in compliance with the License. */ 10 /* You may obtain a copy of the License at */ 11 /* */ 12 /* http://www.apache.org/licenses/LICENSE-2.0 */ 13 /* */ 14 /* Unless required by applicable law or agreed to in writing, software */ 15 /* distributed under the License is distributed on an "AS IS" BASIS, */ 16 /* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */ 17 /* See the License for the specific language governing permissions and */ 18 /* limitations under the License. */ 19 /* */ 20 /* You should have received a copy of the Apache-2.0 license */ 21 /* along with SCIP; see the file LICENSE. If not visit scipopt.org. */ 22 /* */ 23 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ 24 25 /**@file branch_pscost.h 26 * @ingroup BRANCHINGRULES 27 * @brief pseudo costs branching rule 28 * @author Tobias Achterberg 29 * 30 * The pseudo costs branching rule selects the branching variable with respect to the so-called pseudo costs 31 * of the variables. Pseudo costs measure the average gain per unit in the objective function when the variable 32 * was branched on upwards or downwards, resp. The required information is updated at every node of 33 * the solving process. 34 * 35 * The selected variable maximizes the expected gain of the dual bound in the created subtree. 36 * 37 * For a more mathematical description and a comparison between the pseudo costs branching rule 38 * and other branching rules in SCIP, we refer to 39 * 40 * @par 41 * Tobias Achterberg@n 42 * Constraint Integer Programming@n 43 * PhD Thesis, Technische Universität Berlin, 2007@n 44 */ 45 46 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ 47 48 #ifndef __SCIP_BRANCH_PSCOST_H__ 49 #define __SCIP_BRANCH_PSCOST_H__ 50 51 52 #include "scip/def.h" 53 #include "scip/type_retcode.h" 54 #include "scip/type_scip.h" 55 #include "scip/type_var.h" 56 57 #ifdef __cplusplus 58 extern "C" { 59 #endif 60 61 /** creates the pseudo cost branching rule and includes it in SCIP 62 * 63 * @ingroup BranchingRuleIncludes 64 */ 65 SCIP_EXPORT 66 SCIP_RETCODE SCIPincludeBranchrulePscost( 67 SCIP* scip /**< SCIP data structure */ 68 ); 69 70 /**@addtogroup BRANCHINGRULES 71 * 72 * @{ 73 */ 74 75 /** selects a branching variable, due to pseudo cost, from the given candidate array and returns this variable together 76 * with a branching point */ 77 SCIP_EXPORT 78 SCIP_RETCODE SCIPselectBranchVarPscost( 79 SCIP* scip, /**< SCIP data structure */ 80 SCIP_VAR** branchcands, /**< branching candidates */ 81 SCIP_Real* branchcandssol, /**< solution value for the branching candidates */ 82 SCIP_Real* branchcandsscore, /**< array of candidate scores */ 83 int nbranchcands, /**< number of branching candidates */ 84 SCIP_VAR** var, /**< pointer to store the variable to branch on, or NULL if none */ 85 SCIP_Real* brpoint /**< pointer to store the branching point for the branching variable, will be fractional for a discrete variable */ 86 ); 87 88 /** @} */ 89 90 #ifdef __cplusplus 91 } 92 #endif 93 94 #endif 95