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_cardinality.h 26 * @ingroup CONSHDLRS 27 * @brief constraint handler for cardinality constraints 28 * @author Tobias Fischer 29 * 30 */ 31 32 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ 33 34 #ifndef __SCIP_CONS_CARDINALITY_H__ 35 #define __SCIP_CONS_CARDINALITY_H__ 36 37 38 #include "scip/def.h" 39 #include "scip/type_cons.h" 40 #include "scip/type_retcode.h" 41 #include "scip/type_scip.h" 42 #include "scip/type_var.h" 43 44 #ifdef __cplusplus 45 extern "C" { 46 #endif 47 48 /** creates the handler for cardinality constraints and includes it in SCIP 49 * 50 * @ingroup ConshdlrIncludes 51 * */ 52 SCIP_EXPORT 53 SCIP_RETCODE SCIPincludeConshdlrCardinality( 54 SCIP* scip /**< SCIP data structure */ 55 ); 56 57 /**@addtogroup CONSHDLRS 58 * 59 * @{ 60 * 61 * @name Cardinality Constraints 62 * 63 * @{ 64 * 65 * This constraint handler handles cardinality constraints of the form 66 * \f[ 67 * |\mbox{supp}(x)| \leq b 68 * \f] 69 * with integer right-hand side \f$b\f$. Here, \f$|\mbox{supp}(x)|\f$ denotes the number of nonzero entries of the 70 * vector \f$x\f$. 71 * 72 * Cardinality constraints generalize special ordered set of type one (SOS1) constraints in which \f$b = 1\f$. 73 */ 74 75 /** creates and captures an cardinality constraint 76 * 77 * We set the constraint to not be modifable. If the weights are non 78 * NULL, the variables are ordered according to these weights (in 79 * ascending order). 80 * 81 * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons() 82 */ 83 SCIP_EXPORT 84 SCIP_RETCODE SCIPcreateConsCardinality( 85 SCIP* scip, /**< SCIP data structure */ 86 SCIP_CONS** cons, /**< pointer to hold the created constraint */ 87 const char* name, /**< name of constraint */ 88 int nvars, /**< number of variables in the constraint */ 89 SCIP_VAR** vars, /**< array with variables of constraint entries */ 90 int cardval, /**< number of variables allowed to be nonzero */ 91 SCIP_VAR** indvars, /**< indicator variables to indicate which variables may be treated as nonzero 92 * in cardinality constraint, or NULL if indicator variables should be 93 * created automatically */ 94 SCIP_Real* weights, /**< weights determining the variable order, or NULL if variables should be 95 * ordered in the same way they were added to the constraint */ 96 SCIP_Bool initial, /**< should the LP relaxation of constraint be in the initial LP? 97 * Usually set to TRUE. Set to FALSE for 'lazy constraints'. */ 98 SCIP_Bool separate, /**< should the constraint be separated during LP processing? 99 * Usually set to TRUE. */ 100 SCIP_Bool enforce, /**< should the constraint be enforced during node processing? 101 * TRUE for model constraints, FALSE for additional, redundant constraints. */ 102 SCIP_Bool check, /**< should the constraint be checked for feasibility? 103 * TRUE for model constraints, FALSE for additional, redundant constraints. */ 104 SCIP_Bool propagate, /**< should the constraint be propagated during node processing? 105 * Usually set to TRUE. */ 106 SCIP_Bool local, /**< is constraint only valid locally? 107 * Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */ 108 SCIP_Bool dynamic, /**< is constraint subject to aging? 109 * Usually set to FALSE. Set to TRUE for own cuts which 110 * are separated as constraints. */ 111 SCIP_Bool removable, /**< should the relaxation be removed from the LP due to aging or cleanup? 112 * Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */ 113 SCIP_Bool stickingatnode /**< should the constraint always be kept at the node where it was added, even 114 * if it may be moved to a more global node? 115 * Usually set to FALSE. Set to TRUE to for constraints that represent node data. */ 116 ); 117 118 /** creates and captures an cardinality constraint 119 * in its most basic variant, i. e., with all constraint flags set to their default values, which can be set 120 * afterwards using SCIPsetConsFLAGNAME() in scip.h 121 * 122 * @see SCIPcreateConsCardinality() for the default constraint flag configuration 123 * 124 * @warning Do NOT set the constraint to be modifiable manually, because this might lead 125 * to wrong results as the variable array will not be resorted 126 * 127 * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons() 128 */ 129 SCIP_EXPORT 130 SCIP_RETCODE SCIPcreateConsBasicCardinality( 131 SCIP* scip, /**< SCIP data structure */ 132 SCIP_CONS** cons, /**< pointer to hold the created constraint */ 133 const char* name, /**< name of constraint */ 134 int nvars, /**< number of variables in the constraint */ 135 SCIP_VAR** vars, /**< array with variables of constraint entries */ 136 int cardval, /**< number of variables allowed to be nonzero */ 137 SCIP_VAR** indvars, /**< indicator variables to indicate which variables may be treated as nonzero 138 * in cardinality constraint, or NULL if indicator variables should be 139 * created automatically */ 140 SCIP_Real* weights /**< weights determining the variable order, or NULL if variables should be 141 * ordered in the same way they were added to the constraint */ 142 ); 143 144 /** changes cardinality value of cardinality constraint (i.e., right hand side of cardinality constraint) */ 145 SCIP_EXPORT 146 SCIP_RETCODE SCIPchgCardvalCardinality( 147 SCIP* scip, /**< SCIP data structure */ 148 SCIP_CONS* cons, /**< pointer to hold the created constraint */ 149 int cardval /**< number of variables allowed to be nonzero */ 150 ); 151 152 /** adds variable to cardinality constraint, the position is determined by the given weight */ 153 SCIP_EXPORT 154 SCIP_RETCODE SCIPaddVarCardinality( 155 SCIP* scip, /**< SCIP data structure */ 156 SCIP_CONS* cons, /**< constraint */ 157 SCIP_VAR* var, /**< variable to add to the constraint */ 158 SCIP_VAR* indvar, /**< indicator variable to indicate whether variable may be treated as nonzero 159 * in cardinality constraint (or NULL if this variable should be created 160 * automatically) */ 161 SCIP_Real weight /**< weight determining position of variable */ 162 ); 163 164 /** appends variable to cardinality constraint */ 165 SCIP_EXPORT 166 SCIP_RETCODE SCIPappendVarCardinality( 167 SCIP* scip, /**< SCIP data structure */ 168 SCIP_CONS* cons, /**< constraint */ 169 SCIP_VAR* var, /**< variable to add to the constraint */ 170 SCIP_VAR* indvar /**< indicator variable to indicate whether variable may be treated as nonzero 171 * in cardinality constraint (or NULL if this variable should be created 172 * automatically) */ 173 ); 174 175 /** gets number of variables in cardinality constraint */ 176 SCIP_EXPORT 177 int SCIPgetNVarsCardinality( 178 SCIP* scip, /**< SCIP data structure */ 179 SCIP_CONS* cons /**< constraint */ 180 ); 181 182 /** gets array of variables in cardinality constraint */ 183 SCIP_EXPORT 184 SCIP_VAR** SCIPgetVarsCardinality( 185 SCIP* scip, /**< SCIP data structure */ 186 SCIP_CONS* cons /**< constraint data */ 187 ); 188 189 /** gets cardinality value of cardinality constraint (i.e., right hand side of cardinality constraint) */ 190 SCIP_EXPORT 191 int SCIPgetCardvalCardinality( 192 SCIP* scip, /**< SCIP data structure */ 193 SCIP_CONS* cons /**< constraint data */ 194 ); 195 196 /** gets array of weights in cardinality constraint (or NULL if not existent) */ 197 SCIP_EXPORT 198 SCIP_Real* SCIPgetWeightsCardinality( 199 SCIP* scip, /**< SCIP data structure */ 200 SCIP_CONS* cons /**< constraint data */ 201 ); 202 203 /** @} */ 204 205 /** @} */ 206 207 #ifdef __cplusplus 208 } 209 #endif 210 211 #endif 212