Scippy

SCIP

Solving Constraint Integer Programs

Functions
heur_fracdiving.h File Reference
Primal Heuristics

Detailed Description

LP diving heuristic that chooses fixings w.r.t. the fractionalities.

Author
Tobias Achterberg

Diving heuristic: Iteratively fixes some fractional variable and resolves the LP-relaxation, thereby simulating a depth-first-search in the tree. Fractional Diving chooses the variable with the highest fractionality and rounds it to the nearest integer. 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_fracdiving.h.

#include "scip/scip.h"

Go to the source code of this file.

Functions

SCIP_RETCODE SCIPincludeHeurFracdiving (SCIP *scip)
 

Function Documentation

SCIP_RETCODE SCIPincludeHeurFracdiving ( SCIP *  scip)

creates the fracdiving heuristic and includes it in SCIP

Parameters
scipSCIP data structure

Definition at line 253 of file heur_fracdiving.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 SCIP_DECL_DIVESETGETSCORE(), and SCIPincludeDefaultPlugins().