Scippy

SCIP

Solving Constraint Integer Programs

Functions
heur_feaspump.h File Reference
Primal Heuristics

Detailed Description

Objective Feasibility Pump 2.0.

Author
Timo Berthold
Domenico Salvagnin

The fundamental idea of the Feasibility Pump is to construct two sequences of points which hopefully converge to a feasible solution. One sequence consists of LP-feasiblepoints, the other one of integer feasible points. They are produced by alternately rounding an LP-feasible point and solvng an LP that finds a point on the LP polyhedron which is closest to the rounded, integral point (w.r.t. Manhattan distance).

The version implemented in SCIP supports using an Objective Feasibility Pump that uses a convex combination of the Manhattan distance and the original LP objective for reoptimization. It further features Feasibility Pump 2.0 capabilities, hence propagating the fixings for a faster convergence.

Definition in file heur_feaspump.h.

#include "scip/scip.h"

Go to the source code of this file.

Functions

SCIP_RETCODE SCIPincludeHeurFeaspump (SCIP *scip)
 

Function Documentation

SCIP_RETCODE SCIPincludeHeurFeaspump ( SCIP *  scip)

creates the feaspump primal heuristic and includes it in SCIP

Parameters
scipSCIP data structure

Definition at line 1356 of file heur_feaspump.c.

References DEFAULT_ALPHA, DEFAULT_ALPHADIFF, DEFAULT_BEFORECUTS, DEFAULT_COPYCUTS, DEFAULT_CYCLELENGTH, DEFAULT_MAXLOOPS, DEFAULT_MAXLPITEROFS, DEFAULT_MAXLPITERQUOT, DEFAULT_MAXSOLS, DEFAULT_MAXSTALLLOOPS, DEFAULT_MINFLIPS, DEFAULT_NEIGHBORHOODSIZE, DEFAULT_OBJFACTOR, DEFAULT_PERTSOLFOUND, DEFAULT_PERTURBFREQ, DEFAULT_STAGE3, DEFAULT_USEFP20, FALSE, HEUR_DESC, HEUR_DISPCHAR, HEUR_FREQ, HEUR_FREQOFS, HEUR_MAXDEPTH, HEUR_NAME, HEUR_PRIORITY, HEUR_TIMING, HEUR_USESSUBSCIP, NULL, SCIP_CALL, SCIP_OKAY, SCIP_REAL_MAX, SCIPaddBoolParam(), SCIPaddIntParam(), SCIPaddRealParam(), SCIPallocMemory, SCIPincludeHeurBasic(), SCIPsetHeurCopy(), SCIPsetHeurExit(), SCIPsetHeurExitsol(), SCIPsetHeurFree(), SCIPsetHeurInit(), SCIPsetHeurInitsol(), and TRUE.

Referenced by SCIP_DECL_HEURCOPY(), and SCIPincludeDefaultPlugins().