Scippy

SCIP

Solving Constraint Integer Programs

cons_xor.h
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4 /* SCIP --- Solving Constraint Integer Programs */
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24 
25 /**@file cons_xor.h
26  * @ingroup CONSHDLRS
27  * @brief Constraint handler for XOR constraints, \f$rhs = x_1 \oplus x_2 \oplus \dots \oplus x_n\f$
28  * @author Tobias Achterberg
29  * @author Stefan Heinz
30  * @author Michael Winkler
31  *
32  */
33 
34 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
35 
36 #ifndef __SCIP_CONS_XOR_H__
37 #define __SCIP_CONS_XOR_H__
38 
39 
40 #include "scip/def.h"
41 #include "scip/type_cons.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 xor constraints and includes it in SCIP
51  *
52  * @ingroup ConshdlrIncludes
53  * */
54 SCIP_EXPORT
56  SCIP* scip /**< SCIP data structure */
57  );
58 
59 /**@addtogroup CONSHDLRS
60  *
61  * @{
62  *
63  * @name XOR Constraints
64  *
65  * @{
66  *
67  * This constraint handler deals with "xor" constraint. These are constraint of the form:
68  *
69  * \f[
70  * rhs = x_1 \oplus x_2 \oplus \dots \oplus x_n
71  * \f]
72  *
73  * where \f$x_i\f$ is a binary variable for all \f$i\f$ and \f$rhs\f$ is bool. The variables \f$x\f$'s are called
74  * operators. This constraint is satisfied if \f$rhs\f$ is TRUE and an odd number of the operators are TRUE or if the
75  * \f$rhs\f$ is FALSE and a even number of operators are TRUE. Hence, if the sum of \f$rhs\f$ and operators is even.
76  */
77 
78 /** creates and captures an xor constraint
79  *
80  * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
81  */
82 SCIP_EXPORT
84  SCIP* scip, /**< SCIP data structure */
85  SCIP_CONS** cons, /**< pointer to hold the created constraint */
86  const char* name, /**< name of constraint */
87  SCIP_Bool rhs, /**< right hand side of the constraint */
88  int nvars, /**< number of operator variables in the constraint */
89  SCIP_VAR** vars, /**< array with operator variables of constraint */
90  SCIP_Bool initial, /**< should the LP relaxation of constraint be in the initial LP?
91  * Usually set to TRUE. Set to FALSE for 'lazy constraints'. */
92  SCIP_Bool separate, /**< should the constraint be separated during LP processing?
93  * Usually set to TRUE. */
94  SCIP_Bool enforce, /**< should the constraint be enforced during node processing?
95  * TRUE for model constraints, FALSE for additional, redundant constraints. */
96  SCIP_Bool check, /**< should the constraint be checked for feasibility?
97  * TRUE for model constraints, FALSE for additional, redundant constraints. */
98  SCIP_Bool propagate, /**< should the constraint be propagated during node processing?
99  * Usually set to TRUE. */
100  SCIP_Bool local, /**< is constraint only valid locally?
101  * Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */
102  SCIP_Bool modifiable, /**< is constraint modifiable (subject to column generation)?
103  * Usually set to FALSE. In column generation applications, set to TRUE if pricing
104  * adds coefficients to this constraint. */
105  SCIP_Bool dynamic, /**< is constraint subject to aging?
106  * Usually set to FALSE. Set to TRUE for own cuts which
107  * are separated as constraints. */
108  SCIP_Bool removable, /**< should the relaxation be removed from the LP due to aging or cleanup?
109  * Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */
110  SCIP_Bool stickingatnode /**< should the constraint always be kept at the node where it was added, even
111  * if it may be moved to a more global node?
112  * Usually set to FALSE. Set to TRUE to for constraints that represent node data. */
113  );
114 
115 /** creates and captures an xor constraint
116  * in its most basic version, i. e., all constraint flags are set to their basic value as explained for the
117  * method SCIPcreateConsXor(); all flags can be set via SCIPsetConsFLAGNAME-methods in scip.h
118  *
119  * @see SCIPcreateConsXor() for information about the basic constraint flag configuration
120  *
121  * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
122  */
123 SCIP_EXPORT
125  SCIP* scip, /**< SCIP data structure */
126  SCIP_CONS** cons, /**< pointer to hold the created constraint */
127  const char* name, /**< name of constraint */
128  SCIP_Bool rhs, /**< right hand side of the constraint */
129  int nvars, /**< number of operator variables in the constraint */
130  SCIP_VAR** vars /**< array with operator variables of constraint */
131  );
132 
133 /** gets number of variables in xor constraint */
134 SCIP_EXPORT
135 int SCIPgetNVarsXor(
136  SCIP* scip, /**< SCIP data structure */
137  SCIP_CONS* cons /**< constraint data */
138  );
139 
140 /** gets array of variables in xor constraint */
141 SCIP_EXPORT
143  SCIP* scip, /**< SCIP data structure */
144  SCIP_CONS* cons /**< constraint data */
145  );
146 
147 /** gets integer variable in xor constraint */
148 SCIP_EXPORT
150  SCIP* scip, /**< SCIP data structure */
151  SCIP_CONS* cons /**< constraint data */
152  );
153 
154 /** gets the right hand side of the xor constraint */
155 SCIP_EXPORT
157  SCIP* scip, /**< SCIP data structure */
158  SCIP_CONS* cons /**< constraint data */
159  );
160 
161 /** @} */
162 
163 /** @} */
164 
165 #ifdef __cplusplus
166 }
167 #endif
168 
169 #endif
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
SCIP_RETCODE SCIPincludeConshdlrXor(SCIP *scip)
Definition: cons_xor.c:5859
SCIP_RETCODE SCIPcreateConsXor(SCIP *scip, SCIP_CONS **cons, const char *name, SCIP_Bool rhs, int nvars, SCIP_VAR **vars, SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, SCIP_Bool modifiable, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode)
Definition: cons_xor.c:5948
type definitions for return codes for SCIP methods
SCIP_RETCODE SCIPcreateConsBasicXor(SCIP *scip, SCIP_CONS **cons, const char *name, SCIP_Bool rhs, int nvars, SCIP_VAR **vars)
Definition: cons_xor.c:6006
type definitions for SCIP&#39;s main datastructure
type definitions for problem variables
#define SCIP_Bool
Definition: def.h:91
SCIP_Bool SCIPgetRhsXor(SCIP *scip, SCIP_CONS *cons)
Definition: cons_xor.c:6091
SCIP_VAR ** SCIPgetVarsXor(SCIP *scip, SCIP_CONS *cons)
Definition: cons_xor.c:6045
int SCIPgetNVarsXor(SCIP *scip, SCIP_CONS *cons)
Definition: cons_xor.c:6022
common defines and data types used in all packages of SCIP
SCIP_VAR * SCIPgetIntVarXor(SCIP *scip, SCIP_CONS *cons)
Definition: cons_xor.c:6068
type definitions for constraints and constraint handlers