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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
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