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24   	
25   	/**@file   cons_varbound.h
26   	 * @ingroup CONSHDLRS
27   	 * @brief  Constraint handler for variable bound constraints \f$lhs \leq x + c y \leq rhs\f$.
28   	 * @author Tobias Achterberg
29   	 * @author Timo Berthold
30   	 * @author Michael Winkler
31   	 * @author Gerald Gamrath
32   	 * @author Stefan Heinz
33   	 *
34   	 */
35   	
36   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
37   	
38   	#ifndef __SCIP_CONS_VARBOUND_H__
39   	#define __SCIP_CONS_VARBOUND_H__
40   	
41   	
42   	#include "scip/def.h"
43   	#include "scip/type_cons.h"
44   	#include "scip/type_lp.h"
45   	#include "scip/type_retcode.h"
46   	#include "scip/type_scip.h"
47   	#include "scip/type_var.h"
48   	
49   	#ifdef __cplusplus
50   	extern "C" {
51   	#endif
52   	
53   	/** creates the handler for variable bound constraints and includes it in SCIP
54   	 *
55   	 * @ingroup ConshdlrIncludes
56   	 */
57   	SCIP_EXPORT
58   	SCIP_RETCODE SCIPincludeConshdlrVarbound(
59   	   SCIP*                 scip                /**< SCIP data structure */
60   	   );
61   	
62   	/**@addtogroup CONSHDLRS
63   	 *
64   	 * @{
65   	 *
66   	 * @name Variable Bound Constraints
67   	 *
68   	 * @{
69   	 *
70   	 * This constraint handler handles a special type of linear constraints, namely variable bound constraints.
71   	 * A variable bound constraint has the form
72   	 * \f[
73   	 *   lhs \leq x + c y \leq rhs
74   	 * \f]
75   	 * with coefficient \f$c \in Q\f$, \f$lhs\in Q \cup \{-\infty\}\f$, \f$rhs\in Q \cup \{\infty\}\f$,
76   	 * and decision variables \f$x\f$ (non-binary) and \f$y\f$ (binary or integer).
77   	 */
78   	
79   	/** creates and captures a variable bound constraint: lhs <= x + c*y <= rhs
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 SCIPcreateConsVarbound(
85   	   SCIP*                 scip,               /**< SCIP data structure */
86   	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
87   	   const char*           name,               /**< name of constraint */
88   	   SCIP_VAR*             var,                /**< variable x that has variable bound */
89   	   SCIP_VAR*             vbdvar,             /**< binary, integer or implicit integer bounding variable y */
90   	   SCIP_Real             vbdcoef,            /**< coefficient c of bounding variable y */
91   	   SCIP_Real             lhs,                /**< left hand side of variable bound inequality */
92   	   SCIP_Real             rhs,                /**< right hand side of variable bound inequality */
93   	   SCIP_Bool             initial,            /**< should the LP relaxation of constraint be in the initial LP?
94   	                                              *   Usually set to TRUE. Set to FALSE for 'lazy constraints'. */
95   	   SCIP_Bool             separate,           /**< should the constraint be separated during LP processing?
96   	                                              *   Usually set to TRUE. */
97   	   SCIP_Bool             enforce,            /**< should the constraint be enforced during node processing?
98   	                                              *   TRUE for model constraints, FALSE for additional, redundant constraints. */
99   	   SCIP_Bool             check,              /**< should the constraint be checked for feasibility?
100  	                                              *   TRUE for model constraints, FALSE for additional, redundant constraints. */
101  	   SCIP_Bool             propagate,          /**< should the constraint be propagated during node processing?
102  	                                              *   Usually set to TRUE. */
103  	   SCIP_Bool             local,              /**< is constraint only valid locally?
104  	                                              *   Usually set to FALSE. Has to be set to TRUE, e.g., for branching constraints. */
105  	   SCIP_Bool             modifiable,         /**< is constraint modifiable (subject to column generation)?
106  	                                              *   Usually set to FALSE. In column generation applications, set to TRUE if pricing
107  	                                              *   adds coefficients to this constraint. */
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 a varbound constraint
119  	 *  in its most basic version, i. e., all constraint flags are set to their basic value as explained for the
120  	 *  method SCIPcreateConsVarbound(); all flags can be set via SCIPsetConsFLAGNAME-methods in scip.h
121  	 *
122  	 *  @see SCIPcreateConsVarbound() for information about the basic constraint flag configuration
123  	 *
124  	 *  @note the constraint gets captured, hence at one point you have to release it using the method SCIPreleaseCons()
125  	 */
126  	SCIP_EXPORT
127  	SCIP_RETCODE SCIPcreateConsBasicVarbound(
128  	   SCIP*                 scip,               /**< SCIP data structure */
129  	   SCIP_CONS**           cons,               /**< pointer to hold the created constraint */
130  	   const char*           name,               /**< name of constraint */
131  	   SCIP_VAR*             var,                /**< variable x that has variable bound */
132  	   SCIP_VAR*             vbdvar,             /**< binary, integer or implicit integer bounding variable y */
133  	   SCIP_Real             vbdcoef,            /**< coefficient c of bounding variable y */
134  	   SCIP_Real             lhs,                /**< left hand side of variable bound inequality */
135  	   SCIP_Real             rhs                 /**< right hand side of variable bound inequality */
136  	   );
137  	
138  	/** gets left hand side of variable bound constraint lhs <= x + c*y <= rhs */
139  	SCIP_EXPORT
140  	SCIP_Real SCIPgetLhsVarbound(
141  	   SCIP*                 scip,               /**< SCIP data structure */
142  	   SCIP_CONS*            cons                /**< constraint data */
143  	   );
144  	
145  	/** gets right hand side of variable bound constraint lhs <= x + c*y <= rhs */
146  	SCIP_EXPORT
147  	SCIP_Real SCIPgetRhsVarbound(
148  	   SCIP*                 scip,               /**< SCIP data structure */
149  	   SCIP_CONS*            cons                /**< constraint data */
150  	   );
151  	
152  	/** gets bounded variable x of variable bound constraint lhs <= x + c*y <= rhs */
153  	SCIP_EXPORT
154  	SCIP_VAR* SCIPgetVarVarbound(
155  	   SCIP*                 scip,               /**< SCIP data structure */
156  	   SCIP_CONS*            cons                /**< constraint data */
157  	   );
158  	
159  	/** gets bounding variable y of variable bound constraint lhs <= x + c*y <= rhs */
160  	SCIP_EXPORT
161  	SCIP_VAR* SCIPgetVbdvarVarbound(
162  	   SCIP*                 scip,               /**< SCIP data structure */
163  	   SCIP_CONS*            cons                /**< constraint data */
164  	   );
165  	
166  	/** gets bound coefficient c of variable bound constraint lhs <= x + c*y <= rhs */
167  	SCIP_EXPORT
168  	SCIP_Real SCIPgetVbdcoefVarbound(
169  	   SCIP*                 scip,               /**< SCIP data structure */
170  	   SCIP_CONS*            cons                /**< constraint data */
171  	   );
172  	
173  	/** gets the dual solution of the variable bound constraint in the current LP */
174  	SCIP_EXPORT
175  	SCIP_Real SCIPgetDualsolVarbound(
176  	   SCIP*                 scip,               /**< SCIP data structure */
177  	   SCIP_CONS*            cons                /**< constraint data */
178  	   );
179  	
180  	/** gets the dual Farkas value of the variable bound constraint in the current infeasible LP */
181  	SCIP_EXPORT
182  	SCIP_Real SCIPgetDualfarkasVarbound(
183  	   SCIP*                 scip,               /**< SCIP data structure */
184  	   SCIP_CONS*            cons                /**< constraint data */
185  	   );
186  	
187  	/** returns the linear relaxation of the given variable bound constraint; may return NULL if no LP row was yet created;
188  	 *  the user must not modify the row!
189  	 */
190  	SCIP_EXPORT
191  	SCIP_ROW* SCIPgetRowVarbound(
192  	   SCIP*                 scip,               /**< SCIP data structure */
193  	   SCIP_CONS*            cons                /**< constraint data */
194  	   );
195  	
196  	/** cleans up (multi-)aggregations and fixings from varbound constraints */
197  	SCIP_EXPORT
198  	SCIP_RETCODE SCIPcleanupConssVarbound(
199  	   SCIP*                 scip,               /**< SCIP data structure */
200  	   SCIP_Bool             onlychecked,        /**< should only checked constraints be cleaned up? */
201  	   SCIP_Bool*            infeasible,         /**< pointer to return whether the problem was detected to be infeasible */
202  	   int*                  naddconss,          /**< pointer to count number of added (linear) constraints */
203  	   int*                  ndelconss,          /**< pointer to count number of deleted (varbound) constraints */
204  	   int*                  nchgbds             /**< pointer to count number of bound changes */
205  	   );
206  	
207  	/** @} */
208  	
209  	/** @} */
210  	
211  	#ifdef __cplusplus
212  	}
213  	#endif
214  	
215  	#endif
216