Scippy

SCIP

Solving Constraint Integer Programs

heur_veclendiving.h
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1 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2 /* */
3 /* This file is part of the program and library */
4 /* SCIP --- Solving Constraint Integer Programs */
5 /* */
6 /* Copyright (C) 2002-2014 Konrad-Zuse-Zentrum */
7 /* fuer Informationstechnik Berlin */
8 /* */
9 /* SCIP is distributed under the terms of the ZIB Academic License. */
10 /* */
11 /* You should have received a copy of the ZIB Academic License */
12 /* along with SCIP; see the file COPYING. If not email to scip@zib.de. */
13 /* */
14 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
15 
16 /**@file heur_veclendiving.h
17  * @ingroup PRIMALHEURISTICS
18  * @brief LP diving heuristic that rounds variables with long column vectors
19  * @author Tobias Achterberg
20  *
21  * Diving heuristic: Iteratively fixes some fractional variable and resolves the LP-relaxation, thereby simulating a
22  * depth-first-search in the tree. Vectorlength Diving chooses the variable with the smallest ratio of potential
23  * objective change and number of affected constraints and fixes it. One-level backtracking is applied: If the LP gets
24  * infeasible, the last fixings is undone, and the opposite fixing is tried. If this is infeasible, too, the procedure
25  * aborts.
26  */
27 
28 /*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
29 
30 #ifndef __SCIP_HEUR_VECLENDIVING_H__
31 #define __SCIP_HEUR_VECLENDIVING_H__
32 
33 
34 #include "scip/scip.h"
35 
36 #ifdef __cplusplus
37 extern "C" {
38 #endif
39 
40 /** creates the veclendiving heuristic and includes it in SCIP */
41 extern
42 SCIP_RETCODE SCIPincludeHeurVeclendiving(
43  SCIP* scip /**< SCIP data structure */
44  );
45 
46 #ifdef __cplusplus
47 }
48 #endif
49 
50 #endif
51