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_relpscost.h 26 * @ingroup BRANCHINGRULES 27 * @brief reliable pseudo costs branching rule 28 * @author Tobias Achterberg 29 * 30 * The reliable pseudo costs branching rule uses the notion of pseudo costs to measure the expected 31 * gain in the dual bound when branching on a particular variable. 32 * The pseudo cost information is collected during the branch-and-bound search in the same manner as for 33 * the pseudo costs branching rule. 34 * 35 * The reliable pseudo costs branching rule, however, uses a limited number of look-ahead LP-iterations 36 * at the beginning of the search in order to obtain better pseudo cost estimates and make branching decisions in a 37 * sense more "reliable" at an early stage of the search, 38 * at the price of a higher computational cost at the beginning of the search. 39 * 40 * For a more mathematical description and a comparison between the reliable pseudo costs rule and other branching rules 41 * in SCIP, we refer to 42 * 43 * @par 44 * Tobias Achterberg@n 45 * Constraint Integer Programming@n 46 * PhD Thesis, Technische Universität Berlin, 2007@n 47 */ 48 49 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ 50 51 #ifndef __SCIP_BRANCH_RELPSCOST_H__ 52 #define __SCIP_BRANCH_RELPSCOST_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 /** creates the reliable pseudo cost branching rule and includes it in SCIP 66 * 67 * @ingroup BranchingRuleIncludes 68 */ 69 SCIP_EXPORT 70 SCIP_RETCODE SCIPincludeBranchruleRelpscost( 71 SCIP* scip /**< SCIP data structure */ 72 ); 73 74 /**@addtogroup BRANCHINGRULES 75 * 76 * @{ 77 */ 78 79 /** execution reliability pseudo cost branching with the given branching candidates */ 80 SCIP_EXPORT 81 SCIP_RETCODE SCIPexecRelpscostBranching( 82 SCIP* scip, /**< SCIP data structure */ 83 SCIP_VAR** branchcands, /**< branching candidates */ 84 SCIP_Real* branchcandssol, /**< solution value for the branching candidates */ 85 SCIP_Real* branchcandsfrac, /**< fractional part of the branching candidates */ 86 int nbranchcands, /**< number of branching candidates */ 87 SCIP_Bool executebranching, /**< perform a branching step after probing */ 88 SCIP_RESULT* result /**< pointer to the result of the execution */ 89 ); 90 91 /** @} */ 92 93 #ifdef __cplusplus 94 } 95 #endif 96 97 #endif 98