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 cons_logicor.h 26 * @ingroup CONSHDLRS 27 * @brief Constraint handler for logicor constraints \f$1^T x \ge 1\f$ (equivalent to set covering, but algorithms are suited for depth first search). 28 * @author Tobias Achterberg 29 * @author Michael Winkler 30 * 31 */ 32 33 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ 34 35 #ifndef __SCIP_CONS_LOGICOR_H__ 36 #define __SCIP_CONS_LOGICOR_H__ 37 38 39 #include "scip/def.h" 40 #include "scip/type_cons.h" 41 #include "scip/type_lp.h" 42 #include "scip/type_retcode.h" 43 #include "scip/type_scip.h" 44 #include "scip/type_var.h" 45 46 #ifdef __cplusplus 47 extern "C" { 48 #endif 49 50 /** creates the handler for logic or constraints and includes it in SCIP 51 * 52 * @ingroup ConshdlrIncludes 53 * */ 54 SCIP_EXPORT 55 SCIP_RETCODE SCIPincludeConshdlrLogicor( 56 SCIP* scip /**< SCIP data structure */ 57 ); 58 59 /**@addtogroup CONSHDLRS 60 * 61 * @{ 62 * 63 * @name Logicor Constraints 64 * 65 * @{ 66 * 67 * This constraint handler handles a special type of linear constraints, namely 68 * logic or constraints. These are equivalent to set covering constraints, but 69 * are handled by special algorithms which are better suited for depth first search. 70 * For a set of binary variables \f$x_i, i=1,\dots,n\f$, a logic or constraint has the form 71 * \f[ 72 * \sum_{i=1}^n x_i \ge 1. 73 * \f] 74 */ 75 76 /** creates and captures a logic or constraint 77 * 78 * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons() 79 */ 80 SCIP_EXPORT 81 SCIP_RETCODE SCIPcreateConsLogicor( 82 SCIP* scip, /**< SCIP data structure */ 83 SCIP_CONS** cons, /**< pointer to hold the created constraint */ 84 const char* name, /**< name of constraint */ 85 int nvars, /**< number of variables in the constraint */ 86 SCIP_VAR** vars, /**< array with variables of constraint entries */ 87 SCIP_Bool initial, /**< should the LP relaxation of constraint be in the initial LP? 88 * Usually set to TRUE. Set to FALSE for 'lazy constraints'. */ 89 SCIP_Bool separate, /**< should the constraint be separated during LP processing? 90 * Usually set to TRUE. */ 91 SCIP_Bool enforce, /**< should the constraint be enforced during node processing? 92 * TRUE for model constraints, FALSE for additional, redundant constraints. */ 93 SCIP_Bool check, /**< should the constraint be checked for feasibility? 94 * TRUE for model constraints, FALSE for additional, redundant constraints. */ 95 SCIP_Bool propagate, /**< should the constraint be propagated during node processing? 96 * Usually set to TRUE. */ 97 SCIP_Bool local, /**< is constraint only valid locally? 98 * Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */ 99 SCIP_Bool modifiable, /**< is constraint modifiable (subject to column generation)? 100 * Usually set to FALSE. In column generation applications, set to TRUE if pricing 101 * adds coefficients to this constraint. */ 102 SCIP_Bool dynamic, /**< is constraint subject to aging? 103 * Usually set to FALSE. Set to TRUE for own cuts which 104 * are separated as constraints. */ 105 SCIP_Bool removable, /**< should the relaxation be removed from the LP due to aging or cleanup? 106 * Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */ 107 SCIP_Bool stickingatnode /**< should the constraint always be kept at the node where it was added, even 108 * if it may be moved to a more global node? 109 * Usually set to FALSE. Set to TRUE to for constraints that represent node data. */ 110 ); 111 112 /** creates and captures a logicor constraint 113 * in its most basic version, i. e., all constraint flags are set to their basic value as explained for the 114 * method SCIPcreateConsLogicor(); all flags can be set via SCIPsetConsFLAGNAME-methods in scip.h 115 * 116 * @see SCIPcreateConsLogicor() for information about the basic constraint flag configuration 117 * 118 * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons() 119 */ 120 SCIP_EXPORT 121 SCIP_RETCODE SCIPcreateConsBasicLogicor( 122 SCIP* scip, /**< SCIP data structure */ 123 SCIP_CONS** cons, /**< pointer to hold the created constraint */ 124 const char* name, /**< name of constraint */ 125 int nvars, /**< number of variables in the constraint */ 126 SCIP_VAR** vars /**< array with variables of constraint entries */ 127 ); 128 129 /** adds coefficient in logic or constraint */ 130 SCIP_EXPORT 131 SCIP_RETCODE SCIPaddCoefLogicor( 132 SCIP* scip, /**< SCIP data structure */ 133 SCIP_CONS* cons, /**< logicor constraint */ 134 SCIP_VAR* var /**< variable to add to the constraint */ 135 ); 136 137 /** gets number of variables in logic or constraint */ 138 SCIP_EXPORT 139 int SCIPgetNVarsLogicor( 140 SCIP* scip, /**< SCIP data structure */ 141 SCIP_CONS* cons /**< constraint data */ 142 ); 143 144 /** gets array of variables in logic or constraint */ 145 SCIP_EXPORT 146 SCIP_VAR** SCIPgetVarsLogicor( 147 SCIP* scip, /**< SCIP data structure */ 148 SCIP_CONS* cons /**< constraint data */ 149 ); 150 151 /** gets the dual solution of the logic or constraint in the current LP */ 152 SCIP_EXPORT 153 SCIP_Real SCIPgetDualsolLogicor( 154 SCIP* scip, /**< SCIP data structure */ 155 SCIP_CONS* cons /**< constraint data */ 156 ); 157 158 /** gets the dual Farkas value of the logic or constraint in the current infeasible LP */ 159 SCIP_EXPORT 160 SCIP_Real SCIPgetDualfarkasLogicor( 161 SCIP* scip, /**< SCIP data structure */ 162 SCIP_CONS* cons /**< constraint data */ 163 ); 164 165 /** returns the linear relaxation of the given logic or constraint; may return NULL if no LP row was yet created; 166 * the user must not modify the row! 167 */ 168 SCIP_EXPORT 169 SCIP_ROW* SCIPgetRowLogicor( 170 SCIP* scip, /**< SCIP data structure */ 171 SCIP_CONS* cons /**< constraint data */ 172 ); 173 174 /** cleans up (multi-)aggregations and fixings from logicor constraints */ 175 SCIP_EXPORT 176 SCIP_RETCODE SCIPcleanupConssLogicor( 177 SCIP* scip, /**< SCIP data structure */ 178 SCIP_Bool onlychecked, /**< should only checked constraints be cleaned up? */ 179 int* naddconss, /**< pointer to count number of added (linear) constraints */ 180 int* ndelconss, /**< pointer to count number of deleted (logicor) constraints */ 181 int* nchgcoefs /**< pointer to count number of changed coefficients */ 182 ); 183 184 /** @} */ 185 186 /** @} */ 187 188 #ifdef __cplusplus 189 } 190 #endif 191 192 #endif 193