heuristics.h
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31 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
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
89 SCIP_Longint iterlim, /**< nonnegative iteration limit for the LP solves, or -1 for dynamic setting */
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 */
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? */
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
type definitions for miscellaneous datastructures
Definition: struct_scip.h:68
Definition: struct_var.h:207
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)
Definition: heuristics.c:218
Definition: struct_sol.h:73
Definition: struct_misc.h:137
SCIP_RETCODE SCIPaddTrustregionNeighborhoodConstraint(SCIP *scip, SCIP *subscip, SCIP_VAR **subvars, SCIP_Real violpenalty)
Definition: heuristics.c:999
type definitions for primal heuristics
type definitions for SCIP's main datastructure
type definitions for problem variables
Definition: struct_heur.h:97
Definition: struct_heur.h:67
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)
Definition: heuristics.c:925
common defines and data types used in all packages of SCIP
Definition: objbenders.h:43