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27 #include "scip/def.h"
28 #include "scip/type_scip.h"
29 #include "scip/type_heur.h"
30 #include "scip/type_misc.h"
31 #include "scip/type_retcode.h"
32 #include "scip/type_sol.h"
33 #include "scip/type_var.h"
48 * This method performs a diving according to the settings defined by the diving settings @p diveset; Contrary to the
49 * name, SCIP enters probing mode (not diving mode) and dives along a path into the tree. Domain propagation
53 * score defined by the @p diveset and whose solution value has not yet been rendered infeasible by propagation,
56 * The algorithm iteratively selects the the next (unfixed) candidate in the list, until either enough domain changes
57 * or the resolve frequency of the LP trigger an LP resolve (and hence, the set of potential candidates changes),
61 * After the set of remaining candidates is empty or the targeted depth is reached, the node LP is
64 * @see heur_guideddiving.c for an example implementation of a dive set controlling the diving algorithm.
66 * @note the node from where the algorithm is called is checked for a basic LP solution. If the solution
67 * is non-basic, e.g., when barrier without crossover is used, the method returns without performing a dive.
69 * @note currently, when multiple diving heuristics call this method and solve an LP at the same node, only the first
75 SCIP_DIVESET* diveset, /**< settings for diving */
76 SCIP_SOL* worksol, /**< non-NULL working solution */
77 SCIP_HEUR* heur, /**< the calling primal heuristic */
78 SCIP_RESULT* result, /**< SCIP result pointer */
79 SCIP_Bool nodeinfeasible, /**< is the current node known to be infeasible? */
80 SCIP_Longint iterlim, /**< nonnegative iteration limit for the LP solves, or -1 for dynamic setting */
81 SCIP_DIVECONTEXT divecontext /**< context for diving statistics */
87 SCIP* sourcescip, /**< source SCIP data structure */
88 SCIP* subscip, /**< sub-SCIP used by the heuristic */
89 SCIP_HASHMAP* varmap, /**< a hashmap to store the mapping of source variables to the corresponding
92 SCIP_VAR** fixedvars, /**< source variables whose copies should be fixed in the target SCIP environment, or NULL */
93 SCIP_Real* fixedvals, /**< array of fixing values for target SCIP variables, or NULL */
94 int nfixedvars, /**< number of source variables whose copies should be fixed in the target SCIP environment, or NULL */
95 SCIP_Bool uselprows, /**< should the linear relaxation of the problem defined by LP rows be copied? */
96 SCIP_Bool copycuts, /**< should cuts be copied (only if uselprows == FALSE) */
97 SCIP_Bool* success, /**< was the copying successful? */
98 SCIP_Bool* valid /**< pointer to store whether the copying was valid, or NULL */
103 * a trust region constraint measures the deviation from the current incumbent solution \f$x^*\f$ by an auxiliary
108 * Only binary variables are taken into account. The deviation is penalized in the objective function using
111 * @note: the trust region constraint creates an auxiliary variable to penalize the deviation from
112 * the current incumbent solution. This variable can afterwards be accessed using SCIPfindVar() by its name
118 SCIP* subscip, /**< SCIP data structure of the subproblem */
119 SCIP_VAR** subvars, /**< variables of the subproblem, NULL entries are ignored */
120 SCIP_Real violpenalty /**< the penalty for violating the trust region */
type definitions for miscellaneous datastructures
SCIP_EXPORT 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)
type definitions for return codes for SCIP methods
SCIP_EXPORT 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)
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_EXPORT SCIP_RETCODE SCIPaddTrustregionNeighborhoodConstraint(SCIP *scip, SCIP *subscip, SCIP_VAR **subvars, SCIP_Real violpenalty)
common defines and data types used in all packages of SCIP