/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* */ /* This file is part of the program and library */ /* SCIP --- Solving Constraint Integer Programs */ /* */ /* Copyright 2002-2022 Zuse Institute Berlin */ /* */ /* Licensed under the Apache License, Version 2.0 (the "License"); */ /* you may not use this file except in compliance with the License. */ /* You may obtain a copy of the License at */ /* */ /* http://www.apache.org/licenses/LICENSE-2.0 */ /* */ /* Unless required by applicable law or agreed to in writing, software */ /* distributed under the License is distributed on an "AS IS" BASIS, */ /* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */ /* See the License for the specific language governing permissions and */ /* limitations under the License. */ /* */ /* You should have received a copy of the Apache-2.0 license */ /* along with SCIP; see the file LICENSE. If not visit scipopt.org. */ /* */ /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /**@file prop_probing.h * @ingroup PROPAGATORS * @brief probing propagator * @author Tobias Achterberg */ /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/ #ifndef __SCIP_PROP_PROBING_H__ #define __SCIP_PROP_PROBING_H__ #include "scip/def.h" #include "scip/type_lp.h" #include "scip/type_retcode.h" #include "scip/type_scip.h" #include "scip/type_var.h" #ifdef __cplusplus extern "C" { #endif /** creates the probing propagator and includes it in SCIP * * @ingroup PropagatorIncludes */ SCIP_EXPORT SCIP_RETCODE SCIPincludePropProbing( SCIP* scip /**< SCIP data structure */ ); /**@addtogroup PROPAGATORS * * @{ */ /** applies and evaluates probing of a single variable in the given direction and bound */ SCIP_EXPORT SCIP_RETCODE SCIPapplyProbingVar( SCIP* scip, /**< SCIP data structure */ SCIP_VAR** vars, /**< problem variables */ int nvars, /**< number of problem variables */ int probingpos, /**< variable number to apply probing on */ SCIP_BOUNDTYPE boundtype, /**< which bound should be changed */ SCIP_Real bound, /**< which bound should be set */ int maxproprounds, /**< maximal number of propagation rounds (-1: no limit, 0: parameter settings) */ SCIP_Real* impllbs, /**< array to store lower bounds after applying implications and cliques */ SCIP_Real* implubs, /**< array to store upper bounds after applying implications and cliques */ SCIP_Real* proplbs, /**< array to store lower bounds after full propagation */ SCIP_Real* propubs, /**< array to store upper bounds after full propagation */ SCIP_Bool* cutoff /**< pointer to store whether the probing direction is infeasible */ ); /** analyses boundchanges resulting from probing on a variable and performs deduced fixations, aggregations, and domain tightenings * * Given a variable probingvar with domain [l,u] and bound tightening results from reducing the * domain once to [l,leftub] and once to [rightlb,u], the method computes and applies resulting * variable fixations, aggregations, implications, and bound changes. Variable probingvar does not * need to be binary. The whole domain of probingvar need to be covered by the left and right * branches, i.e., we assume leftub >= rightlb for continuous variables or floor(leftub) >= * ceil(rightlb)-1 for discrete variables. Bounds after applying implications and cliques do not * need to be provided, but if they are omitted and probingvar is a binary variable, then already * existing implications may be added. */ SCIP_EXPORT SCIP_RETCODE SCIPanalyzeDeductionsProbing( SCIP* scip, /**< SCIP data structure */ SCIP_VAR* probingvar, /**< the probing variable */ SCIP_Real leftub, /**< upper bound of probing variable in left branch */ SCIP_Real rightlb, /**< lower bound of probing variable in right branch */ int nvars, /**< number of variables which bound changes should be analyzed */ SCIP_VAR** vars, /**< variables which bound changes should be analyzed */ SCIP_Real* leftimpllbs, /**< lower bounds after applying implications and cliques in left branch, or NULL */ SCIP_Real* leftimplubs, /**< upper bounds after applying implications and cliques in left branch, or NULL */ SCIP_Real* leftproplbs, /**< lower bounds after applying domain propagation in left branch */ SCIP_Real* leftpropubs, /**< upper bounds after applying domain propagation in left branch */ SCIP_Real* rightimpllbs, /**< lower bounds after applying implications and cliques in right branch, or NULL */ SCIP_Real* rightimplubs, /**< upper bounds after applying implications and cliques in right branch, or NULL */ SCIP_Real* rightproplbs, /**< lower bounds after applying domain propagation in right branch */ SCIP_Real* rightpropubs, /**< upper bounds after applying domain propagation in right branch */ int* nfixedvars, /**< pointer to counter which is increased by the number of deduced variable fixations */ int* naggrvars, /**< pointer to counter which is increased by the number of deduced variable aggregations */ int* nimplications, /**< pointer to counter which is increased by the number of deduced implications */ int* nchgbds, /**< pointer to counter which is increased by the number of deduced bound tightenings */ SCIP_Bool* cutoff /**< buffer to store whether a cutoff is detected */ ); /** @} */ #ifdef __cplusplus } #endif #endif