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4    	/*         SCIP --- Solving Constraint Integer Programs                      */
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24   	
25   	/**@file   scip_heur.h
26   	 * @ingroup PUBLICCOREAPI
27   	 * @brief  public methods for primal heuristic plugins and divesets
28   	 * @author Tobias Achterberg
29   	 * @author Timo Berthold
30   	 * @author Thorsten Koch
31   	 * @author Alexander Martin
32   	 * @author Marc Pfetsch
33   	 * @author Kati Wolter
34   	 * @author Gregor Hendel
35   	 * @author Leona Gottwald
36   	 */
37   	
38   	/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
39   	
40   	#ifndef __SCIP_SCIP_HEUR_H__
41   	#define __SCIP_SCIP_HEUR_H__
42   	
43   	
44   	#include "scip/def.h"
45   	#include "scip/type_heur.h"
46   	#include "scip/type_result.h"
47   	#include "scip/type_retcode.h"
48   	#include "scip/type_scip.h"
49   	#include "scip/type_timing.h"
50   	#include "scip/type_var.h"
51   	
52   	#ifdef __cplusplus
53   	extern "C" {
54   	#endif
55   	
56   	/**@addtogroup PublicHeuristicMethods
57   	 *
58   	 * @{
59   	 */
60   	
61   	/** creates a primal heuristic and includes it in SCIP.
62   	 *
63   	 *  @note method has all heuristic callbacks as arguments and is thus changed every time a new
64   	 *        callback is added in future releases; consider using SCIPincludeHeurBasic() and setter functions
65   	 *        if you seek for a method which is less likely to change in future releases
66   	 *
67   	 *  @return \ref SCIP_OKAY is returned if everything worked. otherwise a suitable error code is passed. see \ref
68   	 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
69   	 *
70   	 *  @pre This method can be called if @p scip is in one of the following stages:
71   	 *       - \ref SCIP_STAGE_INIT
72   	 *       - \ref SCIP_STAGE_PROBLEM
73   	 */
74   	SCIP_EXPORT
75   	SCIP_RETCODE SCIPincludeHeur(
76   	   SCIP*                 scip,               /**< SCIP data structure */
77   	   const char*           name,               /**< name of primal heuristic */
78   	   const char*           desc,               /**< description of primal heuristic */
79   	   char                  dispchar,           /**< display character of primal heuristic */
80   	   int                   priority,           /**< priority of the primal heuristic */
81   	   int                   freq,               /**< frequency for calling primal heuristic */
82   	   int                   freqofs,            /**< frequency offset for calling primal heuristic */
83   	   int                   maxdepth,           /**< maximal depth level to call heuristic at (-1: no limit) */
84   	   SCIP_HEURTIMING       timingmask,         /**< positions in the node solving loop where heuristic should be executed;
85   	                                              *   see definition of SCIP_HEURTIMING for possible values */
86   	   SCIP_Bool             usessubscip,        /**< does the heuristic use a secondary SCIP instance? */
87   	   SCIP_DECL_HEURCOPY    ((*heurcopy)),      /**< copy method of primal heuristic or NULL if you don't want to copy your plugin into sub-SCIPs */
88   	   SCIP_DECL_HEURFREE    ((*heurfree)),      /**< destructor of primal heuristic */
89   	   SCIP_DECL_HEURINIT    ((*heurinit)),      /**< initialize primal heuristic */
90   	   SCIP_DECL_HEUREXIT    ((*heurexit)),      /**< deinitialize primal heuristic */
91   	   SCIP_DECL_HEURINITSOL ((*heurinitsol)),   /**< solving process initialization method of primal heuristic */
92   	   SCIP_DECL_HEUREXITSOL ((*heurexitsol)),   /**< solving process deinitialization method of primal heuristic */
93   	   SCIP_DECL_HEUREXEC    ((*heurexec)),      /**< execution method of primal heuristic */
94   	   SCIP_HEURDATA*        heurdata            /**< primal heuristic data */
95   	   );
96   	
97   	/** creates a primal heuristic and includes it in SCIP with its most fundamental callbacks.
98   	 *  All non-fundamental (or optional) callbacks
99   	 *  as, e. g., init and exit callbacks, will be set to NULL.
100  	 *  Optional callbacks can be set via specific setter functions, see SCIPsetHeurCopy(), SCIPsetHeurFree(),
101  	 *  SCIPsetHeurInit(), SCIPsetHeurExit(), SCIPsetHeurInitsol(), and SCIPsetHeurExitsol()
102  	 *
103  	*  @note if you want to set all callbacks with a single method call, consider using SCIPincludeHeur() instead
104  	 */
105  	SCIP_EXPORT
106  	SCIP_RETCODE SCIPincludeHeurBasic(
107  	   SCIP*                 scip,               /**< SCIP data structure */
108  	   SCIP_HEUR**           heur,               /**< pointer to the heuristic */
109  	   const char*           name,               /**< name of primal heuristic */
110  	   const char*           desc,               /**< description of primal heuristic */
111  	   char                  dispchar,           /**< display character of primal heuristic */
112  	   int                   priority,           /**< priority of the primal heuristic */
113  	   int                   freq,               /**< frequency for calling primal heuristic */
114  	   int                   freqofs,            /**< frequency offset for calling primal heuristic */
115  	   int                   maxdepth,           /**< maximal depth level to call heuristic at (-1: no limit) */
116  	   SCIP_HEURTIMING       timingmask,         /**< positions in the node solving loop where heuristic should be executed;
117  	                                              *   see definition of SCIP_HEURTIMING for possible values */
118  	   SCIP_Bool             usessubscip,        /**< does the heuristic use a secondary SCIP instance? */
119  	   SCIP_DECL_HEUREXEC    ((*heurexec)),      /**< execution method of primal heuristic */
120  	   SCIP_HEURDATA*        heurdata            /**< primal heuristic data */
121  	   );
122  	
123  	/** sets copy method of primal heuristic */
124  	SCIP_EXPORT
125  	SCIP_RETCODE SCIPsetHeurCopy(
126  	   SCIP*                 scip,               /**< SCIP data structure */
127  	   SCIP_HEUR*            heur,               /**< primal heuristic */
128  	   SCIP_DECL_HEURCOPY    ((*heurcopy))       /**< copy method of primal heuristic or NULL if you don't want to copy your plugin into sub-SCIPs */
129  	   );
130  	
131  	/** sets destructor method of primal heuristic */
132  	SCIP_EXPORT
133  	SCIP_RETCODE SCIPsetHeurFree(
134  	   SCIP*                 scip,               /**< SCIP data structure */
135  	   SCIP_HEUR*            heur,               /**< primal heuristic */
136  	   SCIP_DECL_HEURFREE    ((*heurfree))       /**< destructor of primal heuristic */
137  	   );
138  	
139  	/** sets initialization method of primal heuristic */
140  	SCIP_EXPORT
141  	SCIP_RETCODE SCIPsetHeurInit(
142  	   SCIP*                 scip,               /**< SCIP data structure */
143  	   SCIP_HEUR*            heur,               /**< primal heuristic */
144  	   SCIP_DECL_HEURINIT    ((*heurinit))       /**< initialize primal heuristic */
145  	   );
146  	
147  	/** sets deinitialization method of primal heuristic */
148  	SCIP_EXPORT
149  	SCIP_RETCODE SCIPsetHeurExit(
150  	   SCIP*                 scip,               /**< SCIP data structure */
151  	   SCIP_HEUR*            heur,               /**< primal heuristic */
152  	   SCIP_DECL_HEUREXIT    ((*heurexit))       /**< deinitialize primal heuristic */
153  	   );
154  	
155  	/** sets solving process initialization method of primal heuristic */
156  	SCIP_EXPORT
157  	SCIP_RETCODE SCIPsetHeurInitsol(
158  	   SCIP*                 scip,               /**< SCIP data structure */
159  	   SCIP_HEUR*            heur,               /**< primal heuristic */
160  	   SCIP_DECL_HEURINITSOL ((*heurinitsol))    /**< solving process initialization method of primal heuristic */
161  	   );
162  	
163  	/** sets solving process deinitialization method of primal heuristic */
164  	SCIP_EXPORT
165  	SCIP_RETCODE SCIPsetHeurExitsol(
166  	   SCIP*                 scip,               /**< SCIP data structure */
167  	   SCIP_HEUR*            heur,               /**< primal heuristic */
168  	   SCIP_DECL_HEUREXITSOL ((*heurexitsol))    /**< solving process deinitialization method of primal heuristic */
169  	   );
170  	
171  	/** returns the primal heuristic of the given name, or NULL if not existing */
172  	SCIP_EXPORT
173  	SCIP_HEUR* SCIPfindHeur(
174  	   SCIP*                 scip,               /**< SCIP data structure */
175  	   const char*           name                /**< name of primal heuristic */
176  	   );
177  	
178  	/** returns the array of currently available primal heuristics */
179  	SCIP_EXPORT
180  	SCIP_HEUR** SCIPgetHeurs(
181  	   SCIP*                 scip                /**< SCIP data structure */
182  	   );
183  	
184  	/** returns the number of currently available primal heuristics */
185  	SCIP_EXPORT
186  	int SCIPgetNHeurs(
187  	   SCIP*                 scip                /**< SCIP data structure */
188  	   );
189  	
190  	/** sets the priority of a primal heuristic */
191  	SCIP_EXPORT
192  	SCIP_RETCODE SCIPsetHeurPriority(
193  	   SCIP*                 scip,               /**< SCIP data structure */
194  	   SCIP_HEUR*            heur,               /**< primal heuristic */
195  	   int                   priority            /**< new priority of the primal heuristic */
196  	   );
197  	
198  	/** @} */
199  	
200  	/**@addtogroup PublicDivesetMethods
201  	 *
202  	 * @{
203  	 */
204  	
205  	/** create a diving set associated with a primal heuristic. The primal heuristic needs to be included
206  	 *  before this method can be called. The diveset is installed in the array of divesets of the heuristic
207  	 *  and can be retrieved later by accessing SCIPheurGetDivesets()
208  	 *
209  	 *  @return \ref SCIP_OKAY is returned if everything worked. otherwise a suitable error code is passed. see \ref
210  	 *          SCIP_Retcode "SCIP_RETCODE" for a complete list of error codes.
211  	 *
212  	 *  @pre This method can be called if @p scip is in one of the following stages:
213  	 *       - \ref SCIP_STAGE_INIT
214  	 *       - \ref SCIP_STAGE_PROBLEM
215  	 */
216  	SCIP_EXPORT
217  	SCIP_RETCODE SCIPcreateDiveset(
218  	   SCIP*                 scip,               /**< SCIP data structure */
219  	   SCIP_DIVESET**        diveset,            /**< pointer to created diving heuristic settings, or NULL if not needed */
220  	   SCIP_HEUR*            heur,               /**< primal heuristic to which the diveset belongs */
221  	   const char*           name,               /**< name for the diveset, or NULL if the name of the heuristic should be used */
222  	   SCIP_Real             minreldepth,        /**< minimal relative depth to start diving */
223  	   SCIP_Real             maxreldepth,        /**< maximal relative depth to start diving */
224  	   SCIP_Real             maxlpiterquot,      /**< maximal fraction of diving LP iterations compared to node LP iterations */
225  	   SCIP_Real             maxdiveubquot,      /**< maximal quotient (curlowerbound - lowerbound)/(cutoffbound - lowerbound)
226  	                                              *   where diving is performed (0.0: no limit) */
227  	   SCIP_Real             maxdiveavgquot,     /**< maximal quotient (curlowerbound - lowerbound)/(avglowerbound - lowerbound)
228  	                                              *   where diving is performed (0.0: no limit) */
229  	   SCIP_Real             maxdiveubquotnosol, /**< maximal UBQUOT when no solution was found yet (0.0: no limit) */
230  	   SCIP_Real             maxdiveavgquotnosol,/**< maximal AVGQUOT when no solution was found yet (0.0: no limit) */
231  	   SCIP_Real             lpresolvedomchgquot,/**< percentage of immediate domain changes during probing to trigger LP resolve */
232  	   int                   lpsolvefreq,        /**< LP solve frequency for (0: only if enough domain reductions are found by propagation)*/
233  	   int                   maxlpiterofs,       /**< additional number of allowed LP iterations */
234  	   unsigned int          initialseed,        /**< initial seed for random number generation */
235  	   SCIP_Bool             backtrack,          /**< use one level of backtracking if infeasibility is encountered? */
236  	   SCIP_Bool             onlylpbranchcands,  /**< should only LP branching candidates be considered instead of the slower but
237  	                                              *   more general constraint handler diving variable selection? */
238  	   SCIP_Bool             ispublic,           /**< is this dive set publicly available (ie., can be used by other primal heuristics?) */
239  	   SCIP_Bool             specificsos1score,  /**< should SOS1 variables be scored by the diving heuristics specific score function;
240  	                                              *   otherwise use the score function of the SOS1 constraint handler */
241  	   SCIP_DECL_DIVESETGETSCORE((*divesetgetscore)), /**< method for candidate score and rounding direction */
242  	   SCIP_DECL_DIVESETAVAILABLE((*divesetavailable)) /**< callback to check availability of dive set at the current stage, or NULL if always available */
243  	   );
244  	
245  	/** check specific preconditions for diving, e.g., if an incumbent solution is available */
246  	SCIP_EXPORT
247  	SCIP_RETCODE SCIPisDivesetAvailable(
248  	   SCIP*                 scip,               /**< SCIP data structure */
249  	   SCIP_DIVESET*         diveset,            /**< diving heuristic settings */
250  	   SCIP_Bool*            available           /**< pointer to store if the diving can run at the current solving stage */
251  	   );
252  	
253  	/** @} */
254  	
255  	#ifdef __cplusplus
256  	}
257  	#endif
258  	
259  	#endif
260