presol_symbreak.h File Reference

Detailed Description

presolver for adding symmetry breaking constraints

Author

Marc Pfetsch

Thomas Rehn

Definition in file presol_symbreak.h.

#include "scip/def.h"
#include "scip/type_retcode.h"
#include "scip/type_scip.h"
#include "scip/type_var.h"

Go to the source code of this file.

Functions
SCIP_EXPORT SCIP_RETCODE	SCIPincludePresolSymbreak (SCIP *scip)
SCIP_EXPORT SCIP_RETCODE	SCIPcomputeGroupOrbitsSymbreak (SCIP *scip, SCIP_VAR **permvars, int npermvars, int **perms, int nperms, SCIP_Shortbool *activeperms, int *orbits, int *orbitbegins, int *norbits)

Function Documentation

SCIPincludePresolSymbreak()

SCIP_EXPORT SCIP_RETCODE SCIPincludePresolSymbreak

(

SCIP *

scip

)

creates the symmetry breaking presolver and includes it in SCIP

creates the symbreak presolver and includes it in SCIP

Parameters

scip	SCIP data structure

Definition at line 1315 of file presol_symbreak.c.

References DEFAULT_ADDCONSSTIMING, DEFAULT_ADDSYMRESACKS, DEFAULT_COMPUTEORBITS, DEFAULT_CONSSADDLP, DEFAULT_DETECTORBITOPES, FALSE, NULL, PRESOL_DESC, PRESOL_MAXROUNDS, PRESOL_NAME, PRESOL_PRIORITY, PRESOL_TIMING, SCIP_CALL, SCIP_OKAY, SCIPaddBoolParam(), SCIPaddIntParam(), SCIPallocMemory, SCIPincludePresolBasic(), SCIPsetPresolExit(), SCIPsetPresolExitpre(), SCIPsetPresolFree(), SCIPsetPresolInit(), SCIPsetPresolInitpre(), and TRUE.

Referenced by SCIPincludeDefaultPlugins().

SCIPcomputeGroupOrbitsSymbreak()

SCIP_EXPORT SCIP_RETCODE SCIPcomputeGroupOrbitsSymbreak	(	SCIP *	scip,
		SCIP_VAR **	permvars,
		int	npermvars,
		int **	perms,
		int	nperms,
		SCIP_Shortbool *	activeperms,
		int *	orbits,
		int *	orbitbegins,
		int *	norbits
	)

compute non-trivial orbits of symmetry group

The non-tivial orbits of the group action are stored in the array orbits of length npermvars. This array contains the indices of variables from the permvars array such that variables that are contained in the same orbit appear consecutively in the orbits array. The variables of the i-th orbit have indices orbits[orbitbegins[i]], ... , orbits[orbitbegins[i + 1] - 1]. Note that the description of the orbits ends at orbitbegins[norbits] - 1.

Parameters

scip	SCIP instance
permvars	variables considered by symbreak presolver
npermvars	length of a permutation array
perms	matrix containing in each row a permutation of the symmetry group
nperms	number of permutations encoded in perms
activeperms	array for marking active permutations (or NULL)
orbits	array of non-trivial orbits
orbitbegins	array containing begin positions of new orbits in orbits array
norbits	pointer to number of orbits currently stored in orbits

Definition at line 1393 of file presol_symbreak.c.

References FALSE, NULL, SCIP_CALL, SCIP_OKAY, SCIP_Shortbool, SCIPallocBufferArray, SCIPfreeBufferArray, and TRUE.

Referenced by propagateOrbitalFixing(), and tryAddSymmetryHandlingConss().