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4    	/*         SCIP --- Solving Constraint Integer Programs                      */
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24   	
25   	/**@file   cons_logicor.h
26   	 * @ingroup CONSHDLRS
27   	 * @brief  Constraint handler for logicor constraints \f$1^T x \ge 1\f$ (equivalent to set covering, but algorithms are suited for depth first search).
28   	 * @author Tobias Achterberg
29   	 * @author Michael Winkler
30   	 *
31   	 */
32   	
33   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
34   	
35   	#ifndef __SCIP_CONS_LOGICOR_H__
36   	#define __SCIP_CONS_LOGICOR_H__
37   	
38   	
39   	#include "scip/def.h"
40   	#include "scip/type_cons.h"
41   	#include "scip/type_lp.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 logic or constraints and includes it in SCIP
51   	 *
52   	 * @ingroup ConshdlrIncludes
53   	 * */
54   	SCIP_EXPORT
55   	SCIP_RETCODE SCIPincludeConshdlrLogicor(
56   	   SCIP*                 scip                /**< SCIP data structure */
57   	   );
58   	
59   	/**@addtogroup CONSHDLRS
60   	 *
61   	 * @{
62   	 *
63   	 * @name Logicor Constraints
64   	 *
65   	 * @{
66   	 *
67   	 * This constraint handler handles a special type of linear constraints, namely
68   	 * logic or constraints. These are equivalent to set covering constraints, but
69   	 * are handled by special algorithms which are better suited for depth first search.
70   	 * For a set of binary variables \f$x_i, i=1,\dots,n\f$, a logic or constraint has the form
71   	 * \f[
72   	 *   \sum_{i=1}^n x_i \ge 1.
73   	 * \f]
74   	 */
75   	
76   	/** creates and captures a logic or constraint
77   	 *
78   	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
79   	 */
80   	SCIP_EXPORT
81   	SCIP_RETCODE SCIPcreateConsLogicor(
82   	   SCIP*                 scip,               /**< SCIP data structure */
83   	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
84   	   const char*           name,               /**< name of constraint */
85   	   int                   nvars,              /**< number of variables in the constraint */
86   	   SCIP_VAR**            vars,               /**< array with variables of constraint entries */
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             modifiable,         /**< is constraint modifiable (subject to column generation)?
100  	                                              *   Usually set to FALSE. In column generation applications, set to TRUE if pricing
101  	                                              *   adds coefficients to this constraint. */
102  	   SCIP_Bool             dynamic,            /**< is constraint subject to aging?
103  	                                              *   Usually set to FALSE. Set to TRUE for own cuts which
104  	                                              *   are separated as constraints. */
105  	   SCIP_Bool             removable,          /**< should the relaxation be removed from the LP due to aging or cleanup?
106  	                                              *   Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */
107  	   SCIP_Bool             stickingatnode      /**< should the constraint always be kept at the node where it was added, even
108  	                                              *   if it may be moved to a more global node?
109  	                                              *   Usually set to FALSE. Set to TRUE to for constraints that represent node data. */
110  	   );
111  	
112  	/** creates and captures a logicor constraint
113  	 *  in its most basic version, i. e., all constraint flags are set to their basic value as explained for the
114  	 *  method SCIPcreateConsLogicor(); all flags can be set via SCIPsetConsFLAGNAME-methods in scip.h
115  	 *
116  	 *  @see SCIPcreateConsLogicor() for information about the basic constraint flag configuration
117  	 *
118  	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
119  	 */
120  	SCIP_EXPORT
121  	SCIP_RETCODE SCIPcreateConsBasicLogicor(
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  	   );
128  	
129  	/** adds coefficient in logic or constraint */
130  	SCIP_EXPORT
131  	SCIP_RETCODE SCIPaddCoefLogicor(
132  	   SCIP*                 scip,               /**< SCIP data structure */
133  	   SCIP_CONS*            cons,               /**< logicor constraint */
134  	   SCIP_VAR*             var                 /**< variable to add to the constraint */
135  	   );
136  	
137  	/** gets number of variables in logic or constraint */
138  	SCIP_EXPORT
139  	int SCIPgetNVarsLogicor(
140  	   SCIP*                 scip,               /**< SCIP data structure */
141  	   SCIP_CONS*            cons                /**< constraint data */
142  	   );
143  	
144  	/** gets array of variables in logic or constraint */
145  	SCIP_EXPORT
146  	SCIP_VAR** SCIPgetVarsLogicor(
147  	   SCIP*                 scip,               /**< SCIP data structure */
148  	   SCIP_CONS*            cons                /**< constraint data */
149  	   );
150  	
151  	/** gets the dual solution of the logic or constraint in the current LP */
152  	SCIP_EXPORT
153  	SCIP_Real SCIPgetDualsolLogicor(
154  	   SCIP*                 scip,               /**< SCIP data structure */
155  	   SCIP_CONS*            cons                /**< constraint data */
156  	   );
157  	
158  	/** gets the dual Farkas value of the logic or constraint in the current infeasible LP */
159  	SCIP_EXPORT
160  	SCIP_Real SCIPgetDualfarkasLogicor(
161  	   SCIP*                 scip,               /**< SCIP data structure */
162  	   SCIP_CONS*            cons                /**< constraint data */
163  	   );
164  	
165  	/** returns the linear relaxation of the given logic or constraint; may return NULL if no LP row was yet created;
166  	 *  the user must not modify the row!
167  	 */
168  	SCIP_EXPORT
169  	SCIP_ROW* SCIPgetRowLogicor(
170  	   SCIP*                 scip,               /**< SCIP data structure */
171  	   SCIP_CONS*            cons                /**< constraint data */
172  	   );
173  	
174  	/** cleans up (multi-)aggregations and fixings from logicor constraints */
175  	SCIP_EXPORT
176  	SCIP_RETCODE SCIPcleanupConssLogicor(
177  	   SCIP*                 scip,               /**< SCIP data structure */
178  	   SCIP_Bool             onlychecked,        /**< should only checked constraints be cleaned up? */
179  	   int*                  naddconss,          /**< pointer to count number of added (linear) constraints */
180  	   int*                  ndelconss,          /**< pointer to count number of deleted (logicor) constraints */
181  	   int*                  nchgcoefs           /**< pointer to count number of changed coefficients */
182  	   );
183  	
184  	/** @} */
185  	
186  	/** @} */
187  	
188  	#ifdef __cplusplus
189  	}
190  	#endif
191  	
192  	#endif
193