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24   	
25   	/**@file   cons_sos2.h
26   	 * @ingroup CONSHDLRS
27   	 * @brief  constraint handler for SOS type 2 constraints
28   	 * @author Marc Pfetsch
29   	 *
30   	 */
31   	
32   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
33   	
34   	#ifndef __SCIP_CONS_SOS2_H__
35   	#define __SCIP_CONS_SOS2_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 SOS2 constraints and includes it in SCIP
49   	 *
50   	 * @ingroup ConshdlrIncludes
51   	 * */
52   	SCIP_EXPORT
53   	SCIP_RETCODE SCIPincludeConshdlrSOS2(
54   	   SCIP*                 scip                /**< SCIP data structure */
55   	   );
56   	
57   	/**@addtogroup CONSHDLRS
58   	 *
59   	 * @{
60   	 *
61   	 * @name Specially Ordered Set (SOS) Type 2 Constraints
62   	 *
63   	 * @{
64   	 *
65   	 * A specially ordered set of type 2 (SOS2) is a sequence of variables such that at most two
66   	 * variables are nonzero and if two variables are nonzero they must be adjacent in the specified
67   	 * sequence. Note that it is in principle allowed that a variable appears twice, but it then can be
68   	 * fixed to 0 if it is at least two apart in the sequence.
69   	 */
70   	
71   	/** creates and captures an SOS2 constraint
72   	 *
73   	 *  We set the constraint to not be modifable. If the weights are non
74   	 *  NULL, the variables are ordered according to these weights (in
75   	 *  ascending order).
76   	 *
77   	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
78   	 */
79   	SCIP_EXPORT
80   	SCIP_RETCODE SCIPcreateConsSOS2(
81   	   SCIP*                 scip,               /**< SCIP data structure */
82   	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
83   	   const char*           name,               /**< name of constraint */
84   	   int                   nvars,              /**< number of variables in the constraint */
85   	   SCIP_VAR**            vars,               /**< array with variables of constraint entries */
86   	   SCIP_Real*            weights,            /**< weights determining the variable order, or NULL if natural order should be used */
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 a SOS2 constraint with all constraint flags set to their default values.
110  	 *
111  	 *  @warning Do NOT set the constraint to be modifiable manually, because this might lead
112  	 *  to wrong results as the variable array will not be resorted
113  	 *
114  	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
115  	 */
116  	SCIP_EXPORT
117  	SCIP_RETCODE SCIPcreateConsBasicSOS2(
118  	   SCIP*                 scip,               /**< SCIP data structure */
119  	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
120  	   const char*           name,               /**< name of constraint */
121  	   int                   nvars,              /**< number of variables in the constraint */
122  	   SCIP_VAR**            vars,               /**< array with variables of constraint entries */
123  	   SCIP_Real*            weights             /**< weights determining the variable order, or NULL if natural order should be used */
124  	   );
125  	
126  	/** adds variable to SOS2 constraint, the position is determined by the given weight */
127  	SCIP_EXPORT
128  	SCIP_RETCODE SCIPaddVarSOS2(
129  	   SCIP*                 scip,               /**< SCIP data structure */
130  	   SCIP_CONS*            cons,               /**< constraint */
131  	   SCIP_VAR*             var,                /**< variable to add to the constraint */
132  	   SCIP_Real             weight              /**< weight determining position of variable */
133  	   );
134  	
135  	/** appends variable to SOS2 constraint */
136  	SCIP_EXPORT
137  	SCIP_RETCODE SCIPappendVarSOS2(
138  	   SCIP*                 scip,               /**< SCIP data structure */
139  	   SCIP_CONS*            cons,               /**< constraint */
140  	   SCIP_VAR*             var                 /**< variable to add to the constraint */
141  	   );
142  	
143  	/** gets number of variables in SOS2 constraint */
144  	SCIP_EXPORT
145  	int SCIPgetNVarsSOS2(
146  	   SCIP*                 scip,               /**< SCIP data structure */
147  	   SCIP_CONS*            cons                /**< constraint */
148  	   );
149  	
150  	/** gets array of variables in SOS2 constraint */
151  	SCIP_EXPORT
152  	SCIP_VAR** SCIPgetVarsSOS2(
153  	   SCIP*                 scip,               /**< SCIP data structure */
154  	   SCIP_CONS*            cons                /**< constraint data */
155  	   );
156  	
157  	/** gets array of weights in SOS2 constraint (or NULL if not existent) */
158  	SCIP_EXPORT
159  	SCIP_Real* SCIPgetWeightsSOS2(
160  	   SCIP*                 scip,               /**< SCIP data structure */
161  	   SCIP_CONS*            cons                /**< constraint data */
162  	   );
163  	
164  	/** @} */
165  	
166  	/** @} */
167  	
168  	#ifdef __cplusplus
169  	}
170  	#endif
171  	
172  	#endif
173