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 objbenders.cpp 26 * @brief C++ wrapper for the Benders' decomposition plugins 27 * @author Stephen J. Maher 28 */ 29 30 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ 31 32 #include <cassert> 33 34 #include "objbenders.h" 35 36 37 38 39 /* 40 * Data structures 41 */ 42 43 /** Benders' decomposition data */ 44 struct SCIP_BendersData 45 { 46 scip::ObjBenders* objbenders; /**< the Benders' decomposition object */ 47 SCIP_Bool deleteobject; /**< should the Benders' decomposition object be deleted when benders is freed? */ 48 }; 49 50 51 52 53 /* 54 * Callback methods of the Benders' decomposition framework 55 */ 56 57 extern "C" 58 { 59 60 /** copy method for Benders' decomposition plugins (called when SCIP copies plugins) */ 61 static 62 SCIP_DECL_BENDERSCOPY(bendersCopyObj) 63 { /*lint --e{715}*/ 64 SCIP_BENDERSDATA* bendersdata; 65 66 assert(scip != NULL); 67 68 bendersdata = SCIPbendersGetData(benders); 69 assert(bendersdata != NULL); 70 assert(bendersdata->objbenders != NULL); 71 assert(bendersdata->objbenders->scip_ != scip); 72 73 if( bendersdata->objbenders->iscloneable() ) 74 { 75 scip::ObjBenders* newobjbenders; 76 newobjbenders = dynamic_cast<scip::ObjBenders*> (bendersdata->objbenders->clone(scip)); 77 78 /* call include method of Benders' decomposition object */ 79 SCIP_CALL( SCIPincludeObjBenders(scip, newobjbenders, TRUE) ); 80 } 81 82 return SCIP_OKAY; 83 } 84 85 /** destructor of Benders' decomposition to free user data (called when SCIP is exiting) */ 86 static 87 SCIP_DECL_BENDERSFREE(bendersFreeObj) 88 { /*lint --e{715}*/ 89 SCIP_BENDERSDATA* bendersdata; 90 91 bendersdata = SCIPbendersGetData(benders); 92 assert(bendersdata != NULL); 93 assert(bendersdata->objbenders != NULL); 94 assert(bendersdata->objbenders->scip_ == scip); 95 96 /* call virtual method of benders object */ 97 SCIP_CALL( bendersdata->objbenders->scip_free(scip, benders) ); 98 99 /* free benders object */ 100 if( bendersdata->deleteobject ) 101 delete bendersdata->objbenders; 102 103 /* free benders data */ 104 delete bendersdata; 105 SCIPbendersSetData(benders, NULL); /*lint !e64*/ 106 107 return SCIP_OKAY; 108 } 109 110 111 /** initialization method of Benders' decomposition (called after problem was transformed) */ 112 static 113 SCIP_DECL_BENDERSINIT(bendersInitObj) 114 { /*lint --e{715}*/ 115 SCIP_BENDERSDATA* bendersdata; 116 117 bendersdata = SCIPbendersGetData(benders); 118 assert(bendersdata != NULL); 119 assert(bendersdata->objbenders != NULL); 120 assert(bendersdata->objbenders->scip_ == scip); 121 122 /* call virtual method of benders object */ 123 SCIP_CALL( bendersdata->objbenders->scip_init(scip, benders) ); 124 125 return SCIP_OKAY; 126 } 127 128 129 /** deinitialization method of Benders' decomposition (called before transformed problem is freed) */ 130 static 131 SCIP_DECL_BENDERSEXIT(bendersExitObj) 132 { /*lint --e{715}*/ 133 SCIP_BENDERSDATA* bendersdata; 134 135 bendersdata = SCIPbendersGetData(benders); 136 assert(bendersdata != NULL); 137 assert(bendersdata->objbenders != NULL); 138 139 /* call virtual method of benders object */ 140 SCIP_CALL( bendersdata->objbenders->scip_exit(scip, benders) ); 141 142 return SCIP_OKAY; 143 } 144 145 146 /** presolving initialization method of Benders' decomposition (called when presolving is about to begin) */ 147 static 148 SCIP_DECL_BENDERSINITPRE(bendersInitpreObj) 149 { /*lint --e{715}*/ 150 SCIP_BENDERSDATA* bendersdata; 151 152 bendersdata = SCIPbendersGetData(benders); 153 assert(bendersdata != NULL); 154 assert(bendersdata->objbenders != NULL); 155 156 /* call virtual method of benders object */ 157 SCIP_CALL( bendersdata->objbenders->scip_initpre(scip, benders) ); 158 159 return SCIP_OKAY; 160 } 161 162 163 /** presolving deinitialization method of Benders' decomposition (called after presolving has been finished) */ 164 static 165 SCIP_DECL_BENDERSEXITPRE(bendersExitpreObj) 166 { /*lint --e{715}*/ 167 SCIP_BENDERSDATA* bendersdata; 168 169 bendersdata = SCIPbendersGetData(benders); 170 assert(bendersdata != NULL); 171 assert(bendersdata->objbenders != NULL); 172 173 /* call virtual method of benders object */ 174 SCIP_CALL( bendersdata->objbenders->scip_exitpre(scip, benders) ); 175 176 return SCIP_OKAY; 177 } 178 179 180 /** solving process initialization method of Benders' decomposition (called when branch and bound process is about to begin) */ 181 static 182 SCIP_DECL_BENDERSINITSOL(bendersInitsolObj) 183 { /*lint --e{715}*/ 184 SCIP_BENDERSDATA* bendersdata; 185 186 bendersdata = SCIPbendersGetData(benders); 187 assert(bendersdata != NULL); 188 assert(bendersdata->objbenders != NULL); 189 190 /* call virtual method of benders object */ 191 SCIP_CALL( bendersdata->objbenders->scip_initsol(scip, benders) ); 192 193 return SCIP_OKAY; 194 } 195 196 197 /** solving process deinitialization method of Benders' decomposition (called before branch and bound process data is freed) */ 198 static 199 SCIP_DECL_BENDERSEXITSOL(bendersExitsolObj) 200 { /*lint --e{715}*/ 201 SCIP_BENDERSDATA* bendersdata; 202 203 bendersdata = SCIPbendersGetData(benders); 204 assert(bendersdata != NULL); 205 assert(bendersdata->objbenders != NULL); 206 207 /* call virtual method of benders object */ 208 SCIP_CALL( bendersdata->objbenders->scip_exitsol(scip, benders) ); 209 210 return SCIP_OKAY; 211 } 212 213 214 /** method that is called to create the subproblem and register it with the Benders' decomposition structure. */ 215 static 216 SCIP_DECL_BENDERSCREATESUB(bendersCreatesubObj) 217 { /*lint --e{715}*/ 218 SCIP_BENDERSDATA* bendersdata; 219 220 bendersdata = SCIPbendersGetData(benders); 221 assert(bendersdata != NULL); 222 assert(bendersdata->objbenders != NULL); 223 224 /* call virtual method of benders object */ 225 SCIP_CALL( bendersdata->objbenders->scip_createsub(scip, benders, probnumber) ); 226 227 return SCIP_OKAY; 228 } 229 230 231 /** methods called prior to solving the subproblems */ 232 static 233 SCIP_DECL_BENDERSPRESUBSOLVE(bendersPresubsolveObj) 234 { /*lint --e{715}*/ 235 SCIP_BENDERSDATA* bendersdata; 236 237 bendersdata = SCIPbendersGetData(benders); 238 assert(bendersdata != NULL); 239 assert(bendersdata->objbenders != NULL); 240 241 /* call virtual method of benders object */ 242 SCIP_CALL( bendersdata->objbenders->scip_presubsolve(scip, benders, sol, type, checkint, infeasible, auxviol, 243 skipsolve, result) ); 244 245 return SCIP_OKAY; 246 } 247 248 249 /** method called to solve the convex relaxation of an individual subproblem of the Benders' decomposition */ 250 static 251 SCIP_DECL_BENDERSSOLVESUBCONVEX(bendersSolvesubconvexObj) 252 { /*lint --e{715}*/ 253 SCIP_BENDERSDATA* bendersdata; 254 255 bendersdata = SCIPbendersGetData(benders); 256 assert(bendersdata != NULL); 257 assert(bendersdata->objbenders != NULL); 258 259 /* call virtual method of benders object */ 260 SCIP_CALL( bendersdata->objbenders->scip_solvesubconvex(scip, benders, sol, probnumber, onlyconvexcheck, objective, 261 result) ); 262 263 return SCIP_OKAY; 264 } 265 266 267 /** method called to solve an individual subproblem of the Benders' decomposition */ 268 static 269 SCIP_DECL_BENDERSSOLVESUB(bendersSolvesubObj) 270 { /*lint --e{715}*/ 271 SCIP_BENDERSDATA* bendersdata; 272 273 bendersdata = SCIPbendersGetData(benders); 274 assert(bendersdata != NULL); 275 assert(bendersdata->objbenders != NULL); 276 277 /* call virtual method of benders object */ 278 SCIP_CALL( bendersdata->objbenders->scip_solvesub(scip, benders, sol, probnumber, objective, result) ); 279 280 return SCIP_OKAY; 281 } 282 283 284 /** method called after the subproblems are solved in the Benders' decomposition algorithm */ 285 static 286 SCIP_DECL_BENDERSPOSTSOLVE(bendersPostsolveObj) 287 { /*lint --e{715}*/ 288 SCIP_BENDERSDATA* bendersdata; 289 290 bendersdata = SCIPbendersGetData(benders); 291 assert(bendersdata != NULL); 292 assert(bendersdata->objbenders != NULL); 293 294 /* call virtual method of benders object */ 295 SCIP_CALL( bendersdata->objbenders->scip_postsolve(scip, benders, sol, type, mergecands, npriomergecands, 296 nmergecands, checkint, infeasible, merged) ); 297 298 return SCIP_OKAY; 299 } 300 301 302 /** frees an individual subproblem. Called in each iteration of the Benders' decomposition algorithm */ 303 static 304 SCIP_DECL_BENDERSFREESUB(bendersFreesubObj) 305 { /*lint --e{715}*/ 306 SCIP_BENDERSDATA* bendersdata; 307 308 bendersdata = SCIPbendersGetData(benders); 309 assert(bendersdata != NULL); 310 assert(bendersdata->objbenders != NULL); 311 312 /* call virtual method of benders object */ 313 SCIP_CALL( bendersdata->objbenders->scip_freesub(scip, benders, probnumber) ); 314 315 return SCIP_OKAY; 316 } 317 318 319 /** callback method to retrieve the master (subproblem) variable corresponding to the input subproblem (master) variable */ 320 static 321 SCIP_DECL_BENDERSGETVAR(bendersGetvarObj) 322 { /*lint --e{715}*/ 323 SCIP_BENDERSDATA* bendersdata; 324 325 bendersdata = SCIPbendersGetData(benders); 326 assert(bendersdata != NULL); 327 assert(bendersdata->objbenders != NULL); 328 329 /* call virtual method of benders object */ 330 SCIP_CALL( bendersdata->objbenders->scip_getvar(scip, benders, var, mappedvar, probnumber) ); 331 332 return SCIP_OKAY; 333 } 334 335 336 } 337 338 339 /* 340 * Benders' decomposition specific interface methods 341 */ 342 343 /** creates the Benders' decomposition for the given Benders' decomposition object and includes it in SCIP */ 344 SCIP_RETCODE SCIPincludeObjBenders( 345 SCIP* scip, /**< SCIP data structure */ 346 scip::ObjBenders* objbenders, /**< Benders' decomposition object */ 347 SCIP_Bool deleteobject /**< should the Benders' decomposition object be deleted when benders is freed? */ 348 ) 349 { 350 SCIP_BENDERSDATA* bendersdata; 351 352 assert(scip != NULL); 353 assert(objbenders != NULL); 354 assert(objbenders->scip_ == scip); 355 356 /* create obj Benders' decomposition data */ 357 bendersdata = new SCIP_BENDERSDATA; 358 bendersdata->objbenders = objbenders; 359 bendersdata->deleteobject = deleteobject; 360 361 /* include Benders' decomposition */ 362 SCIP_CALL( SCIPincludeBenders(scip, objbenders->scip_name_, objbenders->scip_desc_, 363 objbenders->scip_priority_, objbenders->scip_cutlp_, objbenders->scip_cutpseudo_, 364 objbenders->scip_cutrelax_, objbenders->scip_shareauxvars_, bendersCopyObj, bendersFreeObj, bendersInitObj, 365 bendersExitObj, bendersInitpreObj, bendersExitpreObj, bendersInitsolObj, bendersExitsolObj, bendersGetvarObj, 366 bendersCreatesubObj, bendersPresubsolveObj, bendersSolvesubconvexObj, bendersSolvesubObj, bendersPostsolveObj, 367 bendersFreesubObj, bendersdata) ); /*lint !e429*/ 368 369 return SCIP_OKAY; /*lint !e429*/ 370 } 371 372 /** returns the benders object of the given name, or 0 if not existing */ 373 scip::ObjBenders* SCIPfindObjBenders( 374 SCIP* scip, /**< SCIP data structure */ 375 const char* name /**< name of Benders' decomposition */ 376 ) 377 { 378 SCIP_BENDERS* benders; 379 SCIP_BENDERSDATA* bendersdata; 380 381 benders = SCIPfindBenders(scip, name); 382 if( benders == NULL ) 383 return 0; 384 385 bendersdata = SCIPbendersGetData(benders); 386 assert(bendersdata != NULL); 387 388 return bendersdata->objbenders; 389 } 390 391 /** returns the benders object for the given Benders' decomposition */ 392 scip::ObjBenders* SCIPgetObjBenders( 393 SCIP* scip, /**< SCIP data structure */ 394 SCIP_BENDERS* benders /**< Benders' decomposition */ 395 ) 396 { 397 SCIP_BENDERSDATA* bendersdata; 398 399 assert(scip != NULL); 400 bendersdata = SCIPbendersGetData(benders); 401 assert(bendersdata != NULL); 402 403 return bendersdata->objbenders; 404 } 405