prop_stp.h File Reference

Detailed Description

propagator for Steiner tree problems, using the LP reduced costs

Author

Daniel Rehfeldt

This propagator makes use of the reduced cost of an optimally solved LP relaxation to propagate the variables, see "SCIP-Jack - A solver for STP and variants with parallelization extensions" by Gamrath, Koch, Maher, Rehfeldt and Shinano

Definition in file prop_stp.h.

#include <stdio.h>
#include <stdlib.h>
#include "scip/scip.h"
#include "grph.h"
#include "probdata_stp.h"

Go to the source code of this file.

Functions
SCIP_RETCODE	SCIPincludePropStp (SCIP *scip)
SCIP_RETCODE	fixedgevar (SCIP *scip, SCIP_VAR *edgevar, int *nfixed)
int	SCIPStpNfixedEdges (SCIP *scip)
void	SCIPStpPropGetGraph (SCIP *scip, GRAPH **graph, SCIP_Longint *graphnodenumber)

Function Documentation

SCIPincludePropStp()

SCIP_RETCODE SCIPincludePropStp

(

SCIP *

scip

)

creates the stp propagator and includes it in SCIP

Parameters

scip	SCIP data structure

Definition at line 904 of file prop_stp.c.

References DEFAULT_MAXNWAITINGROUNDS, FALSE, NULL, PROP_DELAY, PROP_DESC, PROP_FREQ, PROP_NAME, PROP_PRIORITY, PROP_TIMING, SCIP_CALL, SCIP_OKAY, SCIPaddBoolParam(), SCIPaddIntParam(), SCIPallocMemory, SCIPincludePropBasic(), SCIPsetPropCopy(), SCIPsetPropExitsol(), SCIPsetPropFree(), and SCIPsetPropInitsol().

Referenced by runShell(), and SCIP_DECL_PROPCOPY().

fixedgevar()

SCIP_RETCODE fixedgevar	(	SCIP *	scip,
		SCIP_VAR *	edgevar,
		int *	nfixed
	)

fix a variable (corresponding to an edge) to zero

Parameters

scip	SCIP data structure
edgevar	the variable to be fixed
nfixed	counter that is incriminated if variable could be fixed

Definition at line 848 of file prop_stp.c.

References NULL, SCIP_CALL, SCIP_OKAY, SCIPchgVarUb(), SCIPvarGetLbLocal(), and SCIPvarGetUbLocal().

Referenced by dualcostVarfixing(), redbasedVarfixing(), and reduce_boundHopRc().

SCIPStpNfixedEdges()

int SCIPStpNfixedEdges

(

SCIP *

scip

)

return total number of arcs fixed by 'fixedgevar' method of this propagator

Parameters

scip	SCIP data structure

Definition at line 865 of file prop_stp.c.

References NULL, SCIPfindProp(), and SCIPpropGetData().

Referenced by SCIP_DECL_HEUREXEC().

SCIPStpPropGetGraph()

void SCIPStpPropGetGraph	(	SCIP *	scip,
		GRAPH **	graph,
		SCIP_Longint *	graphnodenumber
	)

gets propagator graph

Parameters

scip	SCIP data structure
graph	graph data
graphnodenumber	point to b&b node for which graph is valid

Definition at line 883 of file prop_stp.c.

References NULL, SCIPfindProp(), and SCIPpropGetData().