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_allfullstrong.h 26 * @ingroup BRANCHINGRULES 27 * @brief all variables full strong LP branching rule 28 * @author Tobias Achterberg 29 * @author Gerald Gamrath 30 * 31 * The all variables full strong branching rule applies strong branching to every non-fixed variable 32 * at the current node of the branch-and-bound search. The rule selects the candidate 33 * which will cause the highest gain of the dual bound in the created sub-tree among all branching variables. 34 * 35 * For calculating the gain, a look-ahead is performed by solving the child node LPs which will result 36 * from branching on a variable. 37 * 38 * For a more mathematical description and a comparison between the strong branching rule and other branching rules 39 * in SCIP, we refer to 40 * 41 * @par 42 * Tobias Achterberg@n 43 * Constraint Integer Programming@n 44 * PhD Thesis, Technische Universität Berlin, 2007@n 45 * 46 47 */ 48 49 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ 50 51 #ifndef __SCIP_BRANCH_ALLFULLSTRONG_H__ 52 #define __SCIP_BRANCH_ALLFULLSTRONG_H__ 53 54 55 #include "scip/def.h" 56 #include "scip/type_result.h" 57 #include "scip/type_retcode.h" 58 #include "scip/type_scip.h" 59 #include "scip/type_var.h" 60 61 #ifdef __cplusplus 62 extern "C" { 63 #endif 64 65 66 /** 67 * Selects a variable from a set of candidates by strong branching 68 * 69 * @return \ref SCIP_OKAY is returned if everything worked. Otherwise a suitable error code is passed. See \ref 70 * SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes. 71 * 72 * @note The variables in the lpcands array must have a fractional value in the current LP solution 73 */ 74 SCIP_EXPORT 75 SCIP_RETCODE SCIPselectVarPseudoStrongBranching( 76 SCIP* scip, /**< original SCIP data structure */ 77 SCIP_VAR** pseudocands, /**< branching candidates */ 78 SCIP_Bool* skipdown, /**< should down branchings be skipped? */ 79 SCIP_Bool* skipup, /**< should up branchings be skipped? */ 80 int npseudocands, /**< number of branching candidates */ 81 int npriopseudocands, /**< number of priority branching candidates */ 82 int* bestpseudocand, /**< best candidate for branching */ 83 SCIP_Real* bestdown, /**< objective value of the down branch for bestcand */ 84 SCIP_Real* bestup, /**< objective value of the up branch for bestcand */ 85 SCIP_Real* bestscore, /**< score for bestcand */ 86 SCIP_Bool* bestdownvalid, /**< is bestdown a valid dual bound for the down branch? */ 87 SCIP_Bool* bestupvalid, /**< is bestup a valid dual bound for the up branch? */ 88 SCIP_Real* provedbound, /**< proved dual bound for current subtree */ 89 SCIP_RESULT* result /**< result pointer */ 90 ); 91 92 /** creates the all variables full strong LP branching rule and includes it in SCIP */ 93 SCIP_EXPORT 94 SCIP_RETCODE SCIPincludeBranchruleAllfullstrong( 95 SCIP* scip /**< SCIP data structure */ 96 ); 97 98 #ifdef __cplusplus 99 } 100 #endif 101 102 #endif 103