Scippy

SCIP

Solving Constraint Integer Programs

cons_cardinality.h
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1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
5 /* */
6 /* Copyright (C) 2002-2019 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 scip.zib.de. */
13 /* */
14 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
15 
16 /**@file cons_cardinality.h
17  * @ingroup CONSHDLRS
18  * @brief constraint handler for cardinality constraints
19  * @author Tobias Fischer
20  *
21  */
22 
23 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
24 
25 #ifndef __SCIP_CONS_CARDINALITY_H__
26 #define __SCIP_CONS_CARDINALITY_H__
27 
28 
29 #include "scip/def.h"
30 #include "scip/type_cons.h"
31 #include "scip/type_retcode.h"
32 #include "scip/type_scip.h"
33 #include "scip/type_var.h"
34 
35 #ifdef __cplusplus
36 extern "C" {
37 #endif
38 
39 /** creates the handler for cardinality constraints and includes it in SCIP
40  *
41  * @ingroup ConshdlrIncludes
42  * */
43 extern
45  SCIP* scip /**< SCIP data structure */
46  );
47 
48 /**@addtogroup CONSHDLRS
49  *
50  * @{
51  *
52  * @name Cardinality Constraints
53  *
54  * @{
55  *
56  * This constraint handler handles cardinality constraints of the form
57  * \f[
58  * |\mbox{supp}(x)| \leq b
59  * \f]
60  * with integer right-hand side \f$b\f$. Here, \f$|\mbox{supp}(x)|\f$ denotes the number of nonzero entries of the
61  * vector \f$x\f$.
62  *
63  * Cardinality constraints generalize special ordered set of type one (SOS1) constraints in which \f$b = 1\f$.
64  */
65 
66 /** creates and captures an cardinality constraint
67  *
68  * We set the constraint to not be modifable. If the weights are non
69  * NULL, the variables are ordered according to these weights (in
70  * ascending order).
71  *
72  * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
73  */
74 extern
76  SCIP* scip, /**< SCIP data structure */
77  SCIP_CONS** cons, /**< pointer to hold the created constraint */
78  const char* name, /**< name of constraint */
79  int nvars, /**< number of variables in the constraint */
80  SCIP_VAR** vars, /**< array with variables of constraint entries */
81  int cardval, /**< number of variables allowed to be nonzero */
82  SCIP_VAR** indvars, /**< indicator variables to indicate which variables may be treated as nonzero
83  * in cardinality constraint, or NULL if indicator variables should be
84  * created automatically */
85  SCIP_Real* weights, /**< weights determining the variable order, or NULL if variables should be
86  * ordered in the same way they were added to the constraint */
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 dynamic, /**< is constraint subject to aging?
100  * Usually set to FALSE. Set to TRUE for own cuts which
101  * are separated as constraints. */
102  SCIP_Bool removable, /**< should the relaxation be removed from the LP due to aging or cleanup?
103  * Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */
104  SCIP_Bool stickingatnode /**< should the constraint always be kept at the node where it was added, even
105  * if it may be moved to a more global node?
106  * Usually set to FALSE. Set to TRUE to for constraints that represent node data. */
107  );
108 
109 /** creates and captures an cardinality constraint
110  * in its most basic variant, i. e., with all constraint flags set to their default values, which can be set
111  * afterwards using SCIPsetConsFLAGNAME() in scip.h
112  *
113  * @see SCIPcreateConsCardinality() for the default constraint flag configuration
114  *
115  * @warning Do NOT set the constraint to be modifiable manually, because this might lead
116  * to wrong results as the variable array will not be resorted
117  *
118  * @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
119  */
120 extern
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  int cardval, /**< number of variables allowed to be nonzero */
128  SCIP_VAR** indvars, /**< indicator variables to indicate which variables may be treated as nonzero
129  * in cardinality constraint, or NULL if indicator variables should be
130  * created automatically */
131  SCIP_Real* weights /**< weights determining the variable order, or NULL if variables should be
132  * ordered in the same way they were added to the constraint */
133  );
134 
135 /** changes cardinality value of cardinality constraint (i.e., right hand side of cardinality constraint) */
136 extern
138  SCIP* scip, /**< SCIP data structure */
139  SCIP_CONS* cons, /**< pointer to hold the created constraint */
140  int cardval /**< number of variables allowed to be nonzero */
141  );
142 
143 /** adds variable to cardinality constraint, the position is determined by the given weight */
144 extern
146  SCIP* scip, /**< SCIP data structure */
147  SCIP_CONS* cons, /**< constraint */
148  SCIP_VAR* var, /**< variable to add to the constraint */
149  SCIP_VAR* indvar, /**< indicator variable to indicate whether variable may be treated as nonzero
150  * in cardinality constraint (or NULL if this variable should be created
151  * automatically) */
152  SCIP_Real weight /**< weight determining position of variable */
153  );
154 
155 /** appends variable to cardinality constraint */
156 extern
158  SCIP* scip, /**< SCIP data structure */
159  SCIP_CONS* cons, /**< constraint */
160  SCIP_VAR* var, /**< variable to add to the constraint */
161  SCIP_VAR* indvar /**< indicator variable to indicate whether variable may be treated as nonzero
162  * in cardinality constraint (or NULL if this variable should be created
163  * automatically) */
164  );
165 
166 /** gets number of variables in cardinality constraint */
167 extern
169  SCIP* scip, /**< SCIP data structure */
170  SCIP_CONS* cons /**< constraint */
171  );
172 
173 /** gets array of variables in cardinality constraint */
174 extern
176  SCIP* scip, /**< SCIP data structure */
177  SCIP_CONS* cons /**< constraint data */
178  );
179 
180 /** gets cardinality value of cardinality constraint (i.e., right hand side of cardinality constraint) */
181 extern
183  SCIP* scip, /**< SCIP data structure */
184  SCIP_CONS* cons /**< constraint data */
185  );
186 
187 /** gets array of weights in cardinality constraint (or NULL if not existent) */
188 extern
190  SCIP* scip, /**< SCIP data structure */
191  SCIP_CONS* cons /**< constraint data */
192  );
193 
194 /* @} */
195 
196 /* @} */
197 
198 #ifdef __cplusplus
199 }
200 #endif
201 
202 #endif
SCIP_RETCODE SCIPaddVarCardinality(SCIP *scip, SCIP_CONS *cons, SCIP_VAR *var, SCIP_VAR *indvar, SCIP_Real weight)
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:53
type definitions for return codes for SCIP methods
SCIP_RETCODE SCIPincludeConshdlrCardinality(SCIP *scip)
type definitions for SCIP&#39;s main datastructure
type definitions for problem variables
int SCIPgetCardvalCardinality(SCIP *scip, SCIP_CONS *cons)
#define SCIP_Bool
Definition: def.h:69
SCIP_Real * SCIPgetWeightsCardinality(SCIP *scip, SCIP_CONS *cons)
SCIP_RETCODE SCIPcreateConsCardinality(SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars, int cardval, SCIP_VAR **indvars, SCIP_Real *weights, SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode)
SCIP_RETCODE SCIPcreateConsBasicCardinality(SCIP *scip, SCIP_CONS **cons, const char *name, int nvars, SCIP_VAR **vars, int cardval, SCIP_VAR **indvars, SCIP_Real *weights)
#define SCIP_Real
Definition: def.h:157
int SCIPgetNVarsCardinality(SCIP *scip, SCIP_CONS *cons)
SCIP_RETCODE SCIPchgCardvalCardinality(SCIP *scip, SCIP_CONS *cons, int cardval)
SCIP_RETCODE SCIPappendVarCardinality(SCIP *scip, SCIP_CONS *cons, SCIP_VAR *var, SCIP_VAR *indvar)
SCIP_VAR ** SCIPgetVarsCardinality(SCIP *scip, SCIP_CONS *cons)
common defines and data types used in all packages of SCIP
type definitions for constraints and constraint handlers