Scippy

SCIP

Solving Constraint Integer Programs

heur_shifting.h
Go to the documentation of this file.
1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
5 /* */
6 /* Copyright (c) 2002-2024 Zuse Institute Berlin (ZIB) */
7 /* */
8 /* Licensed under the Apache License, Version 2.0 (the "License"); */
9 /* you may not use this file except in compliance with the License. */
10 /* You may obtain a copy of the License at */
11 /* */
12 /* http://www.apache.org/licenses/LICENSE-2.0 */
13 /* */
14 /* Unless required by applicable law or agreed to in writing, software */
15 /* distributed under the License is distributed on an "AS IS" BASIS, */
16 /* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */
17 /* See the License for the specific language governing permissions and */
18 /* limitations under the License. */
19 /* */
20 /* You should have received a copy of the Apache-2.0 license */
21 /* along with SCIP; see the file LICENSE. If not visit scipopt.org. */
22 /* */
23 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24 
25 /**@file heur_shifting.h
26  * @ingroup PRIMALHEURISTICS
27  * @brief LP rounding heuristic that tries to recover from intermediate infeasibilities and shifts continuous variables
28  * @author Tobias Achterberg
29  *
30  * This heuristic is similar to the Rounding heuristic (see @ref heur_rounding.h), but it tries to continue in the case
31  * that no rounding can decrease the violation of a linear constraint. In this case, the value of a continuous variable
32  * or an integer variable with integral value will be shifted in order to decrease the violation of the constraint. To
33  * avoid cycling, the procedure terminates after a certain number of non-improving shifts.
34  */
35 
36 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
37 
38 #ifndef __SCIP_HEUR_SHIFTING_H__
39 #define __SCIP_HEUR_SHIFTING_H__
40 
41 #include "scip/def.h"
42 #include "scip/type_retcode.h"
43 #include "scip/type_scip.h"
44 
45 #ifdef __cplusplus
46 extern "C" {
47 #endif
48 
49 /** creates the shifting heuristic and includes it in SCIP
50  *
51  * @ingroup PrimalHeuristicIncludes
52  */
53 SCIP_EXPORT
55  SCIP* scip /**< SCIP data structure */
56  );
57 
58 #ifdef __cplusplus
59 }
60 #endif
61 
62 #endif
SCIP_RETCODE SCIPincludeHeurShifting(SCIP *scip)
enum SCIP_Retcode SCIP_RETCODE
Definition: type_retcode.h:63
type definitions for return codes for SCIP methods
type definitions for SCIP&#39;s main datastructure
common defines and data types used in all packages of SCIP