cons_lop.h File Reference

Detailed Description

constraint handler for linear ordering constraints

Author

Marc Pfetsch

This constraint ensures that a given square matrix of binary variables corresponds to a tournament, i.e., it is an acyclic orientation of the complete graph. This encodes a linear order as follows. The rows and columns correspond to the elements of the set to be ordered. A variable x[i][j] is 1 if and only if element i appears before j in the order.

In this constraint handler we only add the symmetry equations and separate the triangle inequalities yielding a correct IP model.

The variables on the diagonal are ignored.

Definition in file cons_lop.h.

#include <scip/scip.h>

Go to the source code of this file.

Functions
SCIP_RETCODE	SCIPincludeConshdlrLOP (SCIP *scip)
SCIP_RETCODE	SCIPcreateConsLOP (SCIP *scip, SCIP_CONS **cons, const char *name, int n, SCIP_VAR ***vars, SCIP_Bool initial, SCIP_Bool separate, SCIP_Bool enforce, SCIP_Bool check, SCIP_Bool propagate, SCIP_Bool local, SCIP_Bool modifiable, SCIP_Bool dynamic, SCIP_Bool removable, SCIP_Bool stickingatnode)

Function Documentation

SCIPincludeConshdlrLOP()

SCIP_RETCODE SCIPincludeConshdlrLOP

(

SCIP *

scip

)

creates the handler for linear ordering constraints and includes it in SCIP

Parameters

scip	SCIP data structure

Definition at line 1255 of file cons_lop.c.

References CONSHDLR_CHECKPRIORITY, CONSHDLR_DELAYPROP, CONSHDLR_DELAYSEPA, CONSHDLR_DESC, CONSHDLR_EAGERFREQ, CONSHDLR_ENFOPRIORITY, CONSHDLR_NAME, CONSHDLR_NEEDSCONS, CONSHDLR_PROP_TIMING, CONSHDLR_PROPFREQ, CONSHDLR_SEPAFREQ, CONSHDLR_SEPAPRIORITY, NULL, SCIP_CALL, SCIP_OKAY, SCIPincludeConshdlrBasic(), SCIPsetConshdlrCopy(), SCIPsetConshdlrDelete(), SCIPsetConshdlrExit(), SCIPsetConshdlrInitlp(), SCIPsetConshdlrPrint(), SCIPsetConshdlrProp(), SCIPsetConshdlrResprop(), SCIPsetConshdlrSepa(), and SCIPsetConshdlrTrans().

Referenced by main(), and SCIP_DECL_CONSHDLRCOPY().

SCIPcreateConsLOP()

SCIP_RETCODE SCIPcreateConsLOP	(	SCIP *	scip,
		SCIP_CONS **	cons,
		const char *	name,
		int	n,
		SCIP_VAR ***	vars,
		SCIP_Bool	initial,
		SCIP_Bool	separate,
		SCIP_Bool	enforce,
		SCIP_Bool	check,
		SCIP_Bool	propagate,
		SCIP_Bool	local,
		SCIP_Bool	modifiable,
		SCIP_Bool	dynamic,
		SCIP_Bool	removable,
		SCIP_Bool	stickingatnode
	)

creates and captures a linear ordering constraint

Parameters

scip	SCIP data structure
cons	pointer to hold the created constraint
name	name of constraint
n	number of elements
vars	n x n matrix of binary variables
initial	should the LP relaxation of constraint be in the initial LP?
separate	should the constraint be separated during LP processing?
enforce	should the constraint be enforced during node processing?
check	should the constraint be checked for feasibility?
propagate	should the constraint be propagated during node processing?
local	is constraint only valid locally?
modifiable	is constraint modifiable (subject to column generation)?
dynamic	is constraint subject to aging?
removable	should the relaxation be removed from the LP due to aging or cleanup?
stickingatnode	should the constraint always be kept at the node where it was added, even if it may be moved to a more global node?

Definition at line 1283 of file cons_lop.c.

References CONSHDLR_NAME, NULL, SCIP_CALL, SCIP_OKAY, SCIP_PLUGINNOTFOUND, SCIPallocBlockMemory, SCIPallocBlockMemoryArray, SCIPcreateCons(), SCIPerrorMessage, SCIPfindConshdlr(), and separate().

Referenced by SCIP_DECL_CONSCOPY(), and SCIP_DECL_READERREAD().