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 objpricer.h 26 * @brief C++ wrapper for variable pricers 27 * @author Tobias Achterberg 28 */ 29 30 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ 31 32 #ifndef __SCIP_OBJPRICER_H__ 33 #define __SCIP_OBJPRICER_H__ 34 35 #include <cstring> 36 #include <utility> 37 38 #include "scip/scip.h" 39 #include "objscip/objprobcloneable.h" 40 41 namespace scip 42 { 43 44 /** @brief C++ wrapper for variable pricer 45 * 46 * This class defines the interface for variable pricer implemented in C++. Note that there is a pure virtual 47 * function (this function has to be implemented). This function is: scip_redcost(). 48 * 49 * - \ref PRICER "Instructions for implementing a variable pricer" 50 * - \ref type_pricer.h "Corresponding C interface" 51 */ 52 class ObjPricer : public ObjProbCloneable 53 { 54 public: 55 /*lint --e{1540}*/ 56 57 /** SCIP data structure */ 58 SCIP* scip_; 59 60 /** name of the variable pricer */ 61 char* scip_name_; 62 63 /** description of the variable pricer */ 64 char* scip_desc_; 65 66 /** default priority of the variable pricer */ 67 const int scip_priority_; 68 69 /** should the pricer be delayed until no other pricers or already existing problem variables with negative reduced 70 * costs are found? 71 */ 72 const SCIP_Bool scip_delay_; 73 74 /** default constructor */ 75 ObjPricer( 76 SCIP* scip, /**< SCIP data structure */ 77 const char* name, /**< name of variable pricer */ 78 const char* desc, /**< description of variable pricer */ 79 int priority, /**< priority of the variable pricer */ 80 SCIP_Bool delay /**< should the pricer be delayed until no other pricers or already existing 81 * problem variables with negative reduced costs are found? 82 * if this is set to FALSE it may happen that the pricer produces columns 83 * that already exist in the problem (which are also priced in by the 84 * default problem variable pricing in the same round) 85 */ 86 ) 87 : scip_(scip), 88 scip_name_(0), 89 scip_desc_(0), 90 scip_priority_(priority), 91 scip_delay_(delay) 92 { 93 /* the macro SCIPduplicateMemoryArray does not need the first argument: */ 94 SCIP_CALL_ABORT( SCIPduplicateMemoryArray(scip_, &scip_name_, name, std::strlen(name)+1) ); 95 SCIP_CALL_ABORT( SCIPduplicateMemoryArray(scip_, &scip_desc_, desc, std::strlen(desc)+1) ); 96 } 97 98 /** copy constructor */ 99 ObjPricer(const ObjPricer& o) : ObjPricer(o.scip_, o.scip_name_, o.scip_desc_, o.scip_priority_, o.scip_delay_) {} 100 101 /** move constructor */ 102 ObjPricer(ObjPricer&& o) 103 : scip_(o.scip_), scip_name_(0), scip_desc_(0), scip_priority_(o.scip_priority_), scip_delay_(o.scip_delay_) 104 { 105 std::swap(scip_name_, o.scip_name_); 106 std::swap(scip_desc_, o.scip_desc_); 107 } 108 109 /** destructor */ 110 virtual ~ObjPricer() 111 { 112 /* the macro SCIPfreeMemoryArray does not need the first argument: */ 113 /*lint --e{64}*/ 114 SCIPfreeMemoryArray(scip_, &scip_name_); 115 SCIPfreeMemoryArray(scip_, &scip_desc_); 116 } 117 118 /** assignment of polymorphic classes causes slicing and is therefore disabled. */ 119 ObjPricer& operator=(const ObjPricer& o) = delete; 120 121 /** assignment of polymorphic classes causes slicing and is therefore disabled. */ 122 ObjPricer& operator=(ObjPricer&& o) = delete; 123 124 /** destructor of variable pricer to free user data (called when SCIP is exiting) 125 * 126 * @see SCIP_DECL_PRICERFREE(x) in @ref type_pricer.h 127 */ 128 virtual SCIP_DECL_PRICERFREE(scip_free) 129 { /*lint --e{715}*/ 130 return SCIP_OKAY; 131 } 132 133 /** initialization method of variable pricer (called after problem was transformed) 134 * 135 * @see SCIP_DECL_PRICERINIT(x) in @ref type_pricer.h 136 */ 137 virtual SCIP_DECL_PRICERINIT(scip_init) 138 { /*lint --e{715}*/ 139 return SCIP_OKAY; 140 } 141 142 /** deinitialization method of variable pricer (called before transformed problem is freed) 143 * 144 * @see SCIP_DECL_PRICEREXIT(x) in @ref type_pricer.h 145 */ 146 virtual SCIP_DECL_PRICEREXIT(scip_exit) 147 { /*lint --e{715}*/ 148 return SCIP_OKAY; 149 } 150 151 /** solving process initialization method of variable pricer (called when branch and bound process is about to begin) 152 * 153 * @see SCIP_DECL_PRICERINITSOL(x) in @ref type_pricer.h 154 */ 155 virtual SCIP_DECL_PRICERINITSOL(scip_initsol) 156 { /*lint --e{715}*/ 157 return SCIP_OKAY; 158 } 159 160 /** solving process deinitialization method of variable pricer (called before branch and bound process data is freed) 161 * 162 * @see SCIP_DECL_PRICEREXITSOL(x) in @ref type_pricer.h 163 */ 164 virtual SCIP_DECL_PRICEREXITSOL(scip_exitsol) 165 { /*lint --e{715}*/ 166 return SCIP_OKAY; 167 } 168 169 /** reduced cost pricing method of variable pricer for feasible LPs 170 * 171 * @see SCIP_DECL_PRICERREDCOST(x) in @ref type_pricer.h 172 */ 173 virtual SCIP_DECL_PRICERREDCOST(scip_redcost) = 0; 174 175 /** farkas pricing method of variable pricer for infeasible LPs 176 * 177 * @see SCIP_DECL_PRICERFARKAS(x) in @ref type_pricer.h 178 */ 179 virtual SCIP_DECL_PRICERFARKAS(scip_farkas) 180 { /*lint --e{715}*/ 181 return SCIP_OKAY; 182 } 183 }; 184 185 } /* namespace scip */ 186 187 188 189 /** creates the variable pricer for the given variable pricer object and includes it in SCIP 190 * 191 * The method should be called in one of the following ways: 192 * 193 * 1. The user is resposible of deleting the object: 194 * SCIP_CALL( SCIPcreate(&scip) ); 195 * ... 196 * MyPricer* mypricer = new MyPricer(...); 197 * SCIP_CALL( SCIPincludeObjPricer(scip, &mypricer, FALSE) ); 198 * ... 199 * SCIP_CALL( SCIPfree(&scip) ); 200 * delete mypricer; // delete pricer AFTER SCIPfree() ! 201 * 202 * 2. The object pointer is passed to SCIP and deleted by SCIP in the SCIPfree() call: 203 * SCIP_CALL( SCIPcreate(&scip) ); 204 * ... 205 * SCIP_CALL( SCIPincludeObjPricer(scip, new MyPricer(...), TRUE) ); 206 * ... 207 * SCIP_CALL( SCIPfree(&scip) ); // destructor of MyPricer is called here 208 */ 209 SCIP_EXPORT 210 SCIP_RETCODE SCIPincludeObjPricer( 211 SCIP* scip, /**< SCIP data structure */ 212 scip::ObjPricer* objpricer, /**< variable pricer object */ 213 SCIP_Bool deleteobject /**< should the pricer object be deleted when pricer is freed? */ 214 ); 215 216 /** returns the variable pricer object of the given name, or 0 if not existing */ 217 SCIP_EXPORT 218 scip::ObjPricer* SCIPfindObjPricer( 219 SCIP* scip, /**< SCIP data structure */ 220 const char* name /**< name of variable pricer */ 221 ); 222 223 /** returns the variable pricer object for the given pricer */ 224 SCIP_EXPORT 225 scip::ObjPricer* SCIPgetObjPricer( 226 SCIP* scip, /**< SCIP data structure */ 227 SCIP_PRICER* pricer /**< pricer */ 228 ); 229 230 #endif 231