Scippy

SCIP

Solving Constraint Integer Programs

cons_cardinality.h
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2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
5 /* */
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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
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
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
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
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
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
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
178  SCIP* scip, /**< SCIP data structure */
179  SCIP_CONS* cons /**< constraint */
180  );
181 
182 /** gets array of variables in cardinality constraint */
183 SCIP_EXPORT
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
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
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
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:63
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:93
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:186
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