Scippy

SCIP

Solving Constraint Integer Programs

Functions
heur_linesearchdiving.h File Reference
Primal Heuristics

Detailed Description

LP diving heuristic that fixes variables with a large difference to their root solution.

Author
Tobias Achterberg

Diving heuristic: Iteratively fixes some fractional variable and resolves the LP-relaxation, thereby simulating a depth-first-search in the tree. Line search diving chooses the variable with the greatest difference of its root LP solution and the current LP solution, hence, the variable that developed most. It is fixed to the next integer in the direction it developed. One-level backtracking is applied: If the LP gets infeasible, the last fixing is undone, and the opposite fixing is tried. If this is infeasible, too, the procedure aborts.

Definition in file heur_linesearchdiving.h.

#include "scip/scip.h"

Go to the source code of this file.

Functions

SCIP_RETCODE SCIPincludeHeurLinesearchdiving (SCIP *scip)
 

Function Documentation

SCIP_RETCODE SCIPincludeHeurLinesearchdiving ( SCIP *  scip)

creates the linesearchdiving primal heuristic and includes it in SCIP

Parameters
scipSCIP data structure

Definition at line 257 of file heur_linesearchdiving.c.

References DEFAULT_BACKTRACK, DEFAULT_LPRESOLVEDOMCHGQUOT, DEFAULT_LPSOLVEFREQ, DEFAULT_MAXDIVEAVGQUOT, DEFAULT_MAXDIVEAVGQUOTNOSOL, DEFAULT_MAXDIVEUBQUOT, DEFAULT_MAXDIVEUBQUOTNOSOL, DEFAULT_MAXLPITEROFS, DEFAULT_MAXLPITERQUOT, DEFAULT_MAXRELDEPTH, DEFAULT_MINRELDEPTH, DEFAULT_ONLYLPBRANCHCANDS, DIVESET_DIVETYPES, HEUR_DESC, HEUR_DISPCHAR, HEUR_FREQ, HEUR_FREQOFS, HEUR_MAXDEPTH, HEUR_NAME, HEUR_PRIORITY, HEUR_TIMING, HEUR_USESSUBSCIP, NULL, SCIP_CALL, SCIP_OKAY, SCIPallocMemory, SCIPcreateDiveset(), SCIPincludeHeurBasic(), SCIPsetHeurCopy(), SCIPsetHeurExit(), SCIPsetHeurFree(), and SCIPsetHeurInit().

Referenced by SCIPincludeDefaultPlugins().