1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /*                                                                           */
3 /*                  This file is part of the program and library             */
4 /*         SCIP --- Solving Constraint Integer Programs                      */
5 /*                                                                           */
6 /*    Copyright (C) 2002-2021 Konrad-Zuse-Zentrum                            */
7 /*                            fuer Informationstechnik Berlin                */
8 /*                                                                           */
9 /*  SCIP is distributed under the terms of the ZIB Academic License.         */
10 /*                                                                           */
11 /*  You should have received a copy of the ZIB Academic License              */
12 /*  along with SCIP; see the file COPYING. If not visit scipopt.org.         */
13 /*                                                                           */
14 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
15 
16 /**@file   cons_and.h
17  * @ingroup CONSHDLRS
18  * @brief  Constraint handler for AND constraints,  \f$r = x_1 \wedge x_2 \wedge \dots  \wedge x_n\f$
19  * @author Tobias Achterberg
20  * @author Stefan Heinz
21  * @author Michael Winkler
22  *
23  */
24 
25 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
26 
27 #ifndef __SCIP_CONS_AND_H__
28 #define __SCIP_CONS_AND_H__
29 
30 
31 #include "scip/def.h"
32 #include "scip/type_cons.h"
33 #include "scip/type_retcode.h"
34 #include "scip/type_scip.h"
35 #include "scip/type_var.h"
36 
37 #ifdef __cplusplus
38 extern "C" {
39 #endif
40 
41 /** creates the handler for and constraints and includes it in SCIP
42  *
43  * @ingroup ConshdlrIncludes
44  * */
45 SCIP_EXPORT
46 SCIP_RETCODE SCIPincludeConshdlrAnd(
47    SCIP*                 scip                /**< SCIP data structure */
48    );
49 
50 /**@addtogroup CONSHDLRS
51  *
52  * @{
53  *
54  * @name AND Constraints
55  *
56  * @{
57  *
58  * This constraint handler deals with AND-constraints. These are constraint of the form:
59  *
60  * \f[
61  *    r = x_1 \wedge x_2 \wedge \dots  \wedge x_n
62  * \f]
63  *
64  * where \f$x_i\f$ is a binary variable for all \f$i\f$. Hence, \f$r\f$ is also of binary type. The variable \f$r\f$ is
65  * called resultant and the \f$x\f$'s operators.
66  */
67 
68 /** creates and captures an and constraint
69  *
70  *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
71  */
72 SCIP_EXPORT
73 SCIP_RETCODE SCIPcreateConsAnd(
74    SCIP*                 scip,               /**< SCIP data structure */
75    SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
76    const char*           name,               /**< name of constraint */
77    SCIP_VAR*             resvar,             /**< resultant variable of the operation */
78    int                   nvars,              /**< number of operator variables in the constraint */
79    SCIP_VAR**            vars,               /**< array with operator variables of constraint */
80    SCIP_Bool             initial,            /**< should the LP relaxation of constraint be in the initial LP?
81                                               *   Usually set to TRUE. Set to FALSE for 'lazy constraints'. */
82    SCIP_Bool             separate,           /**< should the constraint be separated during LP processing?
83                                               *   Usually set to TRUE. */
84    SCIP_Bool             enforce,            /**< should the constraint be enforced during node processing?
85                                               *   TRUE for model constraints, FALSE for additional, redundant constraints. */
86    SCIP_Bool             check,              /**< should the constraint be checked for feasibility?
87                                               *   TRUE for model constraints, FALSE for additional, redundant constraints. */
88    SCIP_Bool             propagate,          /**< should the constraint be propagated during node processing?
89                                               *   Usually set to TRUE. */
90    SCIP_Bool             local,              /**< is constraint only valid locally?
91                                               *   Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */
92    SCIP_Bool             modifiable,         /**< is constraint modifiable (subject to column generation)?
93                                               *   Usually set to FALSE. In column generation applications, set to TRUE if pricing
94                                               *   adds coefficients to this constraint. */
95    SCIP_Bool             dynamic,            /**< is constraint subject to aging?
96                                               *   Usually set to FALSE. Set to TRUE for own cuts which
97                                               *   are separated as constraints. */
98    SCIP_Bool             removable,          /**< should the relaxation be removed from the LP due to aging or cleanup?
99                                               *   Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */
100    SCIP_Bool             stickingatnode      /**< should the constraint always be kept at the node where it was added, even
101                                               *   if it may be moved to a more global node?
102                                               *   Usually set to FALSE. Set to TRUE to for constraints that represent node data. */
103    );
104 
105 /** creates and captures an and constraint
106  *  in its most basic version, i. e., all constraint flags are set to their basic value as explained for the
107  *  method SCIPcreateConsAnd(); all flags can be set via SCIPsetConsFLAGNAME-methods in scip.h
108  *
109  *  @see SCIPcreateConsAnd() for information about the basic constraint flag configuration
110  *
111  *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
112  */
113 SCIP_EXPORT
114 SCIP_RETCODE SCIPcreateConsBasicAnd(
115    SCIP*                 scip,               /**< SCIP data structure */
116    SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
117    const char*           name,               /**< name of constraint */
118    SCIP_VAR*             resvar,             /**< resultant variable of the operation */
119    int                   nvars,              /**< number of operator variables in the constraint */
120    SCIP_VAR**            vars                /**< array with operator variables of constraint */
121    );
122 
123 /** gets number of variables in and constraint */
124 SCIP_EXPORT
125 int SCIPgetNVarsAnd(
126    SCIP*                 scip,               /**< SCIP data structure */
127    SCIP_CONS*            cons                /**< constraint data */
128    );
129 
130 /** gets array of variables in and constraint */
131 SCIP_EXPORT
132 SCIP_VAR** SCIPgetVarsAnd(
133    SCIP*                 scip,               /**< SCIP data structure */
134    SCIP_CONS*            cons                /**< constraint data */
135    );
136 
137 /** gets the resultant variable in and constraint */
138 SCIP_EXPORT
139 SCIP_VAR* SCIPgetResultantAnd(
140    SCIP*                 scip,               /**< SCIP data structure */
141    SCIP_CONS*            cons                /**< constraint data */
142    );
143 
144 /** return if the variables of the AND-constraint are sorted with respect to their indices */
145 SCIP_EXPORT
146 SCIP_Bool SCIPisAndConsSorted(
147    SCIP*                 scip,               /**< SCIP data structure */
148    SCIP_CONS*            cons                /**< constraint data */
149    );
150 
151 /** sort the variables of the AND-constraint with respect to their indices */
152 SCIP_EXPORT
153 SCIP_RETCODE SCIPsortAndCons(
154    SCIP*                 scip,               /**< SCIP data structure */
155    SCIP_CONS*            cons                /**< constraint data */
156    );
157 
158 /** when 'upgrading' the given AND-constraint, should the check flag for the upgraded constraint be set to TRUE, even if
159  *  the check flag of this AND-constraint is set to FALSE?
160  */
161 SCIP_EXPORT
162 SCIP_RETCODE SCIPchgAndConsCheckFlagWhenUpgr(
163    SCIP*                 scip,               /**< SCIP data structure */
164    SCIP_CONS*            cons,               /**< constraint data */
165    SCIP_Bool             flag                /**< should an arising constraint from the given AND-constraint be checked,
166                                               *   even if the check flag of the AND-constraint is set to FALSE
167                                               */
168    );
169 
170 /** when 'upgrading' the given AND-constraint, should the removable flag for the upgraded constraint be set to FALSE,
171  *  even if the removable flag of this AND-constraint is set to TRUE?
172  */
173 SCIP_EXPORT
174 SCIP_RETCODE SCIPchgAndConsRemovableFlagWhenUpgr(
175    SCIP*                 scip,               /**< SCIP data structure */
176    SCIP_CONS*            cons,               /**< constraint data */
177    SCIP_Bool             flag                /**< should an arising constraint from the given AND-constraint be not
178                                               *   removable, even if the removable flag of the AND-constraint is set to
179                                               *   TRUE
180                                               */
181    );
182 
183 /** @} */
184 
185 /** @} */
186 
187 #ifdef __cplusplus
188 }
189 #endif
190 
191 #endif
192