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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* */
/* 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