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24   	
25   	/**@file   cons_orbisack.h
26   	 * @ingroup CONSHDLRS
27   	 * @brief  constraint handler for orbisack constraints
28   	 * @author Christopher Hojny
29   	 *
30   	 * The constraint works on two vectors of variables, which are interpreted as columns of a matrix such that the first
31   	 * column is lexicographically not smaller than the second.
32   	 */
33   	
34   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
35   	
36   	#ifndef __SCIP_CONS_ORBISACK_H__
37   	#define __SCIP_CONS_ORBISACK_H__
38   	
39   	#include "scip/def.h"
40   	#include "scip/type_cons.h"
41   	#include "scip/type_retcode.h"
42   	#include "scip/type_scip.h"
43   	#include "scip/type_sol.h"
44   	#include "scip/type_var.h"
45   	
46   	#ifdef __cplusplus
47   	extern "C" {
48   	#endif
49   	
50   	
51   	/** creates the handler for orbisack constraints and includes it in SCIP
52   	 *
53   	 *  @ingroup ConshdlrIncludes
54   	 */
55   	SCIP_EXPORT
56   	SCIP_RETCODE SCIPincludeConshdlrOrbisack(
57   	   SCIP*                 scip                /**< SCIP data structure */
58   	   );
59   	
60   	/**@addtogroup CONSHDLRS
61   	 *
62   	 * @{
63   	 *
64   	 * @name Orbisack Constraints
65   	 *
66   	 * @{
67   	 *
68   	 * This constraint handler can be used to handle symmetries in certain 0/1-programs. The principle
69   	 * structure is that some variables can be ordered in matrix form with two columns, such that
70   	 * permuting both columns does not change the validity and objective function value of a solution.
71   	 * That is, there exists a permutation symmetry of the program that permutes the variables of the
72   	 * first and second column row-wise.
73   	 *
74   	 * In more mathematical terms the structure has to be as follows: There are 0/1-variables
75   	 * \f$x_{ij}\f$, \f$i \in \{1, \dots, n\}\f$, \f$j \in \{1, 2\}\f$. Permuting columns of
76   	 * \f$x\f$ does not change the validity and objective function value of any feasible solution.
77   	 */
78   	
79   	
80   	/** checks whether a given binary solution is feasible for the orbisack */
81   	SCIP_EXPORT
82   	SCIP_RETCODE SCIPcheckSolutionOrbisack(
83   	   SCIP*                 scip,               /**< SCIP data structure */
84   	   SCIP_SOL*             sol,                /**< solution to check for feasibility */
85   	   SCIP_VAR**            vars1,              /**< variables of first column */
86   	   SCIP_VAR**            vars2,              /**< variables of second column */
87   	   int                   nrows,              /**< number of rows */
88   	   SCIP_Bool             printreason,        /**< whether reason for infeasibility should be printed */
89   	   SCIP_Bool*            feasible            /**< memory address to store whether sol is feasible */
90   	   );
91   	
92   	/** creates and captures a orbisack constraint
93   	 *
94   	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
95   	 */
96   	SCIP_EXPORT
97   	SCIP_RETCODE SCIPcreateConsOrbisack(
98   	   SCIP*                 scip,               /**< SCIP data structure */
99   	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
100  	   const char*           name,               /**< name of constraint */
101  	   SCIP_VAR*const*       vars1,              /**< first column matrix of variables on which the symmetry acts */
102  	   SCIP_VAR*const*       vars2,              /**< second column matrix of variables on which the symmetry acts */
103  	   int                   nrows,              /**< number of rows in variable matrix */
104  	   SCIP_Bool             ispporbisack,       /**< whether the orbisack is a packing/partitioning orbisack */
105  	   SCIP_Bool             isparttype,         /**< whether the orbisack is a partitioning orbisack */
106  	   SCIP_Bool             ismodelcons,        /**< whether the orbisack is a model constraint */
107  	   SCIP_Bool             initial,            /**< should the LP relaxation of constraint be in the initial LP?
108  	                                              *   Usually set to TRUE. Set to FALSE for 'lazy constraints'. */
109  	   SCIP_Bool             separate,           /**< should the constraint be separated during LP processing?
110  	                                              *   Usually set to TRUE. */
111  	   SCIP_Bool             enforce,            /**< should the constraint be enforced during node processing?
112  	                                              *   TRUE for model constraints, FALSE for additional, redundant constraints. */
113  	   SCIP_Bool             check,              /**< should the constraint be checked for feasibility?
114  	                                              *   TRUE for model constraints, FALSE for additional, redundant constraints. */
115  	   SCIP_Bool             propagate,          /**< should the constraint be propagated during node processing?
116  	                                              *   Usually set to TRUE. */
117  	   SCIP_Bool             local,              /**< is constraint only valid locally?
118  	                                              *   Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */
119  	   SCIP_Bool             modifiable,         /**< is constraint modifiable (subject to column generation)?
120  	                                              *   Usually set to FALSE. In column generation applications, set to TRUE if pricing
121  	                                              *   adds coefficients to this constraint. */
122  	   SCIP_Bool             dynamic,            /**< is constraint subject to aging?
123  	                                              *   Usually set to FALSE. Set to TRUE for own cuts which
124  	                                              *   are separated as constraints. */
125  	   SCIP_Bool             removable,          /**< should the relaxation be removed from the LP due to aging or cleanup?
126  	                                              *   Usually set to FALSE. Set to TRUE for 'lazy constraints' and 'user cuts'. */
127  	   SCIP_Bool             stickingatnode      /**< should the constraint always be kept at the node where it was added, even
128  	                                              *   if it may be moved to a more global node?
129  	                                              *   Usually set to FALSE. Set to TRUE to for constraints that represent node data. */
130  	   );
131  	
132  	/** creates and captures an orbisack constraint in its most basic variant
133  	 *
134  	 *  All constraint flags set to their default values, which can be set afterwards using SCIPsetConsFLAGNAME() in scip.h.
135  	 *
136  	 *  @see SCIPcreateConsOrbisack() for the default constraint flag configuration
137  	 *
138  	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
139  	 */
140  	SCIP_EXPORT
141  	SCIP_RETCODE SCIPcreateConsBasicOrbisack(
142  	   SCIP*                 scip,               /**< SCIP data structure */
143  	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
144  	   const char*           name,               /**< name of constraint */
145  	   SCIP_VAR**            vars1,              /**< first column of matrix of variables on which the symmetry acts */
146  	   SCIP_VAR**            vars2,              /**< second column of matrix of variables on which the symmetry acts */
147  	   int                   nrows,              /**< number of rows in constraint matrix */
148  	   SCIP_Bool             ispporbisack,       /**< whether the orbisack is a packing/partitioning orbisack */
149  	   SCIP_Bool             isparttype,         /**< whether the orbisack is a partitioning orbisack */
150  	   SCIP_Bool             ismodelcons         /**< whether the orbisack is a model constraint */
151  	   );
152  	
153  	/** @} */
154  	
155  	/** @} */
156  	
157  	#ifdef __cplusplus
158  	}
159  	#endif
160  	
161  	#endif
162