Scippy

SCIP

Solving Constraint Integer Programs

Functions
heur_randrounding.h File Reference
Primal Heuristics

Detailed Description

randomized LP rounding heuristic which also generates conflicts via an auxiliary probing tree

Author
Gregor Hendel

Randomized LP rounding uses a random variable from a uniform distribution over [0,1] to determine whether the fractional LP value x should be rounded up with probability x - floor(x) or down with probability ceil(x) - x.

This implementation uses domain propagation techniques to tighten the variable domains after every rounding step.

See also
: The most relevant publication is Raghavan & Thompson, "Randomized rounding: A technique for provably good algorithms and algorithmic proofs", Combinatorica 7 (4): 365–374 1987

Definition in file heur_randrounding.h.

#include "scip/scip.h"

Go to the source code of this file.

Functions

SCIP_RETCODE SCIPincludeHeurRandrounding (SCIP *scip)
 

Function Documentation

SCIP_RETCODE SCIPincludeHeurRandrounding ( SCIP *  scip)

creates the rand rounding heuristic and includes it in SCIP

Parameters
scipSCIP data structure

Definition at line 472 of file heur_randrounding.c.

References DEFAULT_MAXPROPROUNDS, DEFAULT_ONCEPERNODE, DEFAULT_PROPAGATEONLYROOT, DEFAULT_USESIMPLEROUNDING, HEUR_DESC, HEUR_DISPCHAR, HEUR_FREQ, HEUR_FREQOFS, HEUR_MAXDEPTH, HEUR_NAME, HEUR_PRIORITY, HEUR_TIMING, HEUR_USESSUBSCIP, NULL, SCIP_CALL, SCIP_OKAY, SCIPaddBoolParam(), SCIPaddIntParam(), SCIPallocMemory, SCIPincludeHeurBasic(), SCIPsetHeurCopy(), SCIPsetHeurExit(), SCIPsetHeurExitsol(), SCIPsetHeurFree(), SCIPsetHeurInit(), SCIPsetHeurInitsol(), and TRUE.

Referenced by SCIP_DECL_HEURCOPY(), SCIP_DECL_HEUREXEC(), and SCIPincludeDefaultPlugins().