1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* */
/* 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 heur_rounding.h
* @ingroup PRIMALHEURISTICS
* @brief LP rounding heuristic that tries to recover from intermediate infeasibilities
* @author Tobias Achterberg
*
* Rounding heuristic that starts from an LP-feasible point and reduces the number of fractional variables by one in
* each step. As long as no LP row is violated, the algorithm iterates over the fractional variables and applies a
* rounding into the direction of fewer locks, updating the activities of the LP rows after each step. If there is a
* violated LP row, the heuristic will try to find a fractional variable that can be rounded in a direction such that
* the violation of the constraint is decreased, using the number of up- and down-locks as a tie breaker. If no
* rounding can decrease the violation of the constraint, the procedure is aborted.
*/
/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
#ifndef __SCIP_HEUR_ROUNDING_H__
#define __SCIP_HEUR_ROUNDING_H__
#include "scip/def.h"
#include "scip/type_retcode.h"
#include "scip/type_scip.h"
#ifdef __cplusplus
extern "C" {
#endif
/** creates the rounding heuristic with infeasibility recovering and includes it in SCIP
*
* @ingroup PrimalHeuristicIncludes
*/
SCIP_EXPORT
SCIP_RETCODE SCIPincludeHeurRounding(
SCIP* scip /**< SCIP data structure */
);
#ifdef __cplusplus
}
#endif
#endif