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36 #include "scip/def.h"
37 #include "scip/type_scip.h"
38 #include "scip/type_heur.h"
39 #include "scip/type_misc.h"
40 #include "scip/type_retcode.h"
41 #include "scip/type_sol.h"
42 #include "scip/type_var.h"
57 * This method performs a diving according to the settings defined by the diving settings @p diveset; Contrary to the
58 * name, SCIP enters probing mode (not diving mode) and dives along a path into the tree. Domain propagation
62 * score defined by the @p diveset and whose solution value has not yet been rendered infeasible by propagation,
65 * The algorithm iteratively selects the the next (unfixed) candidate in the list, until either enough domain changes
66 * or the resolve frequency of the LP trigger an LP resolve (and hence, the set of potential candidates changes),
70 * After the set of remaining candidates is empty or the targeted depth is reached, the node LP is
73 * @see heur_guideddiving.c for an example implementation of a dive set controlling the diving algorithm.
75 * @note the node from where the algorithm is called is checked for a basic LP solution. If the solution
76 * is non-basic, e.g., when barrier without crossover is used, the method returns without performing a dive.
78 * @note currently, when multiple diving heuristics call this method and solve an LP at the same node, only the first
84 SCIP_DIVESET* diveset, /**< settings for diving */
85 SCIP_SOL* worksol, /**< non-NULL working solution */
86 SCIP_HEUR* heur, /**< the calling primal heuristic */
87 SCIP_RESULT* result, /**< SCIP result pointer */
88 SCIP_Bool nodeinfeasible, /**< is the current node known to be infeasible? */
89 SCIP_Longint iterlim, /**< nonnegative iteration limit for the LP solves, or -1 for dynamic setting */
90 SCIP_DIVECONTEXT divecontext /**< context for diving statistics */
96 SCIP* sourcescip, /**< source SCIP data structure */
97 SCIP* subscip, /**< sub-SCIP used by the heuristic */
98 SCIP_HASHMAP* varmap, /**< a hashmap to store the mapping of source variables to the corresponding
101 SCIP_VAR** fixedvars, /**< source variables whose copies should be fixed in the target SCIP environment, or NULL */
102 SCIP_Real* fixedvals, /**< array of fixing values for target SCIP variables, or NULL */
103 int nfixedvars, /**< number of source variables whose copies should be fixed in the target SCIP environment, or NULL */
104 SCIP_Bool uselprows, /**< should the linear relaxation of the problem defined by LP rows be copied? */
105 SCIP_Bool copycuts, /**< should cuts be copied (only if uselprows == FALSE) */
106 SCIP_Bool* success, /**< was the copying successful? */
107 SCIP_Bool* valid /**< pointer to store whether the copying was valid, or NULL */
112 * a trust region constraint measures the deviation from the current incumbent solution \f$x^*\f$ by an auxiliary
117 * Only binary variables are taken into account. The deviation is penalized in the objective function using
120 * @note: the trust region constraint creates an auxiliary variable to penalize the deviation from
121 * the current incumbent solution. This variable can afterwards be accessed using SCIPfindVar() by its name
127 SCIP* subscip, /**< SCIP data structure of the subproblem */
128 SCIP_VAR** subvars, /**< variables of the subproblem, NULL entries are ignored */
129 SCIP_Real violpenalty /**< the penalty for violating the trust region */
type definitions for miscellaneous datastructures
type definitions for return codes for SCIP methods
SCIP_RETCODE SCIPperformGenericDivingAlgorithm(SCIP *scip, SCIP_DIVESET *diveset, SCIP_SOL *worksol, SCIP_HEUR *heur, SCIP_RESULT *result, SCIP_Bool nodeinfeasible, SCIP_Longint iterlim, SCIP_DIVECONTEXT divecontext)
SCIP_RETCODE SCIPaddTrustregionNeighborhoodConstraint(SCIP *scip, SCIP *subscip, SCIP_VAR **subvars, SCIP_Real violpenalty)
type definitions for primal heuristics
type definitions for SCIP's main datastructure
type definitions for problem variables
type definitions for storing primal CIP solutions
SCIP_RETCODE SCIPcopyLargeNeighborhoodSearch(SCIP *sourcescip, SCIP *subscip, SCIP_HASHMAP *varmap, const char *suffix, SCIP_VAR **fixedvars, SCIP_Real *fixedvals, int nfixedvars, SCIP_Bool uselprows, SCIP_Bool copycuts, SCIP_Bool *success, SCIP_Bool *valid)
common defines and data types used in all packages of SCIP