Detailed Description

optimization-based bound tightening propagator

Author: Stefan Weltge; Benjamin Mueller

Definition in file prop_obbt.c.

#include <assert.h>
#include <string.h>
#include "scip/prop_obbt.h"
#include "scip/prop_genvbounds.h"
#include "scip/debug.h"
#include "scip/cons_quadratic.h"
#include "scip/cons_nonlinear.h"
#include "scip/cons_abspower.h"
#include "scip/cons_bivariate.h"

Go to the source code of this file.

Macros
#define	PROP_NAME "obbt"

#define	PROP_DESC "optimization-based bound tightening propagator"

#define	PROP_TIMING SCIP_PROPTIMING_AFTERLPLOOP

#define	PROP_PRIORITY -1000000

#define	PROP_FREQ 0

#define	PROP_DELAY TRUE

#define	DEFAULT_CREATE_GENVBOUNDS TRUE

#define	DEFAULT_FILTERING_NORM TRUE

#define	DEFAULT_APPLY_FILTERROUNDS FALSE

#define	DEFAULT_APPLY_TRIVIALFITLERING TRUE

#define	DEFAULT_GENVBDSDURINGFILTER TRUE

#define	DEFAULT_DUALFEASTOL 1e-9

#define	DEFAULT_CONDITIONLIMIT -1.0

#define	DEFAULT_BOUNDSTREPS 0.001

#define	DEFAULT_FILTERING_MIN 2

#define	DEFAULT_ITLIMITFACTOR 10.0

#define	DEFAULT_MINITLIMIT 5000L

#define	DEFAULT_ONLYNONCONVEXVARS FALSE

#define	DEFAULT_TIGHTINTBOUNDSPROBING TRUE

#define	DEFAULT_TIGHTCONTBOUNDSPROBING FALSE

#define	DEFAULT_ORDERINGALGO 1

#define	OBBT_SCOREBASE 5

#define	GENVBOUND_PROP_NAME "genvbounds"

#define	INTERVALINFTY 1E+43

#define	DEFAULT_SEPARATESOL FALSE

#define	DEFAULT_SEPAMINITER 0

#define	DEFAULT_SEPAMAXITER 10

#define	DEFAULT_GENVBDSDURINGSEPA TRUE

#define	DEFAULT_PROPAGATEFREQ 0

#define	infty2infty(infty1, infty2, val) ((val) >= (infty1) ? (infty2) : (val))

Typedefs
typedef struct Bound	BOUND

Functions
static SCIP_RETCODE	solveLP (SCIP scip, int itlimit, SCIP_Bool error, SCIP_Bool *optimal)

static SCIP_RETCODE	addObjCutoff (SCIP scip, SCIP_PROPDATA propdata)

static SCIP_Bool	varIsFixedLocal (SCIP scip, SCIP_VAR var)

static SCIP_RETCODE	setObjProbing (SCIP scip, SCIP_PROPDATA propdata, BOUND *bound, SCIP_Real coef)

static SCIP_Bool	includeVarGenVBound (SCIP scip, SCIP_VAR var)

static int	getIterationsLeft (SCIP *scip, SCIP_Longint nolditerations, SCIP_Longint itlimit)

static SCIP_Real	getFilterCoef (SCIP scip, SCIP_PROPDATA propdata, SCIP_VAR *var, SCIP_BOUNDTYPE boundtype)

static SCIP_RETCODE	createGenVBound (SCIP scip, SCIP_PROPDATA propdata, BOUND bound, SCIP_Bool found)

static void	exchangeBounds (SCIP_PROPDATA *propdata, int i)

static SCIP_RETCODE	filterExistingLP (SCIP scip, SCIP_PROPDATA propdata, int nfiltered, BOUND currbound)

static SCIP_RETCODE	filterRound (SCIP scip, SCIP_PROPDATA propdata, int itlimit, int nfiltered, SCIP_Real objcoefs, int *objcoefsinds, int nobjcoefs)

static SCIP_RETCODE	filterBounds (SCIP scip, SCIP_PROPDATA propdata, SCIP_Longint itlimit)

static SCIP_RETCODE	applyBoundChgs (SCIP scip, SCIP_PROPDATA propdata, SCIP_RESULT *result)

static SCIP_RETCODE	tightenBoundProbing (SCIP scip, BOUND bound, SCIP_Real newval, SCIP_Bool *tightened)

static	SCIP_DECL_SORTPTRCOMP (compBoundsScore)

static	SCIP_DECL_SORTPTRCOMP (compBoundsBoundtype)

static SCIP_RETCODE	sortBounds (SCIP scip, SCIP_PROPDATA propdata)

static SCIP_Real	evalBound (SCIP scip, BOUND bound)

static int	nextBound (SCIP scip, SCIP_PROPDATA propdata, SCIP_Bool convexphase)

static SCIP_RETCODE	applySeparation (SCIP scip, SCIP_PROPDATA propdata, BOUND currbound, SCIP_Longint nleftiterations, SCIP_Bool *success)

static SCIP_RETCODE	findNewBounds (SCIP scip, SCIP_PROPDATA propdata, SCIP_Longint *nleftiterations, SCIP_Bool convexphase)

static SCIP_RETCODE	applyObbt (SCIP scip, SCIP_PROPDATA propdata, SCIP_Longint itlimit, SCIP_RESULT *result)

static unsigned int	getScore (SCIP scip, BOUND bound, int nlcount, int maxnlcount)

static SCIP_RETCODE	countNLRowVarsNonConvexity (SCIP scip, int nlcounts, SCIP_NLROW *nlrow)

static SCIP_RETCODE	getNLPVarsNonConvexity (SCIP scip, int nlcounts)

static SCIP_Bool	varIsInteresting (SCIP scip, SCIP_VAR var, int nlcount)

static SCIP_RETCODE	initBounds (SCIP scip, SCIP_PROPDATA propdata)

static	SCIP_DECL_PROPINITSOL (propInitsolObbt)

static	SCIP_DECL_PROPEXEC (propExecObbt)

static	SCIP_DECL_PROPRESPROP (propRespropObbt)

static	SCIP_DECL_PROPEXITSOL (propExitsolObbt)

static	SCIP_DECL_PROPFREE (propFreeObbt)

SCIP_RETCODE	SCIPincludePropObbt (SCIP *scip)

Macro Definition Documentation

#define PROP_NAME "obbt"

Definition at line 49 of file prop_obbt.c.

#define PROP_DESC "optimization-based bound tightening propagator"

Definition at line 50 of file prop_obbt.c.

#define PROP_TIMING SCIP_PROPTIMING_AFTERLPLOOP

Definition at line 51 of file prop_obbt.c.

#define PROP_PRIORITY -1000000

propagator priority

Definition at line 52 of file prop_obbt.c.

#define PROP_FREQ 0

propagator frequency

Definition at line 53 of file prop_obbt.c.

#define PROP_DELAY TRUE

should propagation method be delayed, if other propagators found reductions?

Definition at line 54 of file prop_obbt.c.

#define DEFAULT_CREATE_GENVBOUNDS TRUE

should obbt try to provide genvbounds if possible?

Definition at line 58 of file prop_obbt.c.

#define DEFAULT_FILTERING_NORM TRUE

should coefficients in filtering be normalized w.r.t. the domains sizes?

Definition at line 59 of file prop_obbt.c.

#define DEFAULT_APPLY_FILTERROUNDS FALSE

try to filter bounds in so-called filter rounds by solving auxiliary LPs?

Definition at line 62 of file prop_obbt.c.

#define DEFAULT_APPLY_TRIVIALFITLERING TRUE

should obbt try to use the LP solution to filter some bounds?

Definition at line 65 of file prop_obbt.c.

#define DEFAULT_GENVBDSDURINGFILTER TRUE

try to genrate genvbounds during trivial and aggressive filtering?

Definition at line 66 of file prop_obbt.c.

#define DEFAULT_DUALFEASTOL 1e-9

feasibility tolerance for reduced costs used in obbt; this value is used if SCIP's dual feastol is greater

Definition at line 67 of file prop_obbt.c.

#define DEFAULT_CONDITIONLIMIT -1.0

maximum condition limit used in LP solver (-1.0: no limit)

Definition at line 70 of file prop_obbt.c.

#define DEFAULT_BOUNDSTREPS 0.001

minimal relative improve for strengthening bounds

Definition at line 71 of file prop_obbt.c.

#define DEFAULT_FILTERING_MIN 2

minimal number of filtered bounds to apply another filter round

Definition at line 72 of file prop_obbt.c.

#define DEFAULT_ITLIMITFACTOR 10.0

multiple of root node LP iterations used as total LP iteration limit for obbt (<= 0: no limit )

Definition at line 75 of file prop_obbt.c.

#define DEFAULT_MINITLIMIT 5000L

minimum LP iteration limit

Definition at line 78 of file prop_obbt.c.

#define DEFAULT_ONLYNONCONVEXVARS FALSE

only apply obbt on non-convex variables

Definition at line 79 of file prop_obbt.c.

#define DEFAULT_TIGHTINTBOUNDSPROBING TRUE

should bounds of integral variables be tightened during the probing mode?

Definition at line 80 of file prop_obbt.c.

#define DEFAULT_TIGHTCONTBOUNDSPROBING FALSE

should bounds of continuous variables be tightened during the probing mode?

Definition at line 83 of file prop_obbt.c.

#define DEFAULT_ORDERINGALGO 1

which type of ordering algorithm should we use? (0: no, 1: greedy, 2: greedy reverse)

Definition at line 86 of file prop_obbt.c.

#define OBBT_SCOREBASE 5

base that is used to calculate a bounds score value

Definition at line 89 of file prop_obbt.c.

#define GENVBOUND_PROP_NAME "genvbounds"

Definition at line 90 of file prop_obbt.c.

#define INTERVALINFTY 1E+43

value for infinity in interval operations

Definition at line 91 of file prop_obbt.c.

#define DEFAULT_SEPARATESOL FALSE

should the obbt LP solution be separated? note that that by separating solution OBBT will apply all bound tightenings immediatly

Definition at line 93 of file prop_obbt.c.

#define DEFAULT_SEPAMINITER 0

minimum number of iteration spend to separate an obbt LP solution

Definition at line 98 of file prop_obbt.c.

#define DEFAULT_SEPAMAXITER 10

maximum number of iteration spend to separate an obbt LP solution

Definition at line 99 of file prop_obbt.c.

#define DEFAULT_GENVBDSDURINGSEPA TRUE

try to create genvbounds during separation process?

Definition at line 100 of file prop_obbt.c.

#define DEFAULT_PROPAGATEFREQ 0

trigger a propagation round after that many bound tightenings (0: no propagation)

Definition at line 101 of file prop_obbt.c.

#define infty2infty	(	infty1,
		infty2,
		val
	)	((val) >= (infty1) ? (infty2) : (val))

translate from one value of infinity to another

if val is >= infty1, then give infty2, else give val

Definition at line 109 of file prop_obbt.c.

Typedef Documentation

typedef struct Bound BOUND

Definition at line 128 of file prop_obbt.c.

Function Documentation

static SCIP_RETCODE solveLP	(	SCIP *	scip,
		int	itlimit,
		SCIP_Bool *	error,
		SCIP_Bool *	optimal
	)

static

solves the LP and handles errors

Parameters

scip	SCIP data structure
itlimit	maximal number of LP iterations to perform, or -1 for no limit
error	pointer to store whether an unresolved LP error occurred
optimal	was the LP solved to optimalilty?

Definition at line 189 of file prop_obbt.c.

Referenced by filterExistingLP().

static SCIP_RETCODE addObjCutoff	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata
	)

static

adds the objective cutoff to the LP; must be in probing mode

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator

Definition at line 261 of file prop_obbt.c.

static SCIP_Bool varIsFixedLocal	(	SCIP *	scip,
		SCIP_VAR *	var
	)

static

determines, whether a variable is already locally fixed

Parameters

scip	SCIP data structure
var	variable to check

Definition at line 311 of file prop_obbt.c.

static SCIP_RETCODE setObjProbing	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		BOUND *	bound,
		SCIP_Real	coef
	)

static

sets objective to minimize or maximize a single variable

Definition at line 321 of file prop_obbt.c.

Referenced by filterExistingLP().

static SCIP_Bool includeVarGenVBound	(	SCIP *	scip,
		SCIP_VAR *	var
	)

static

determines whether variable should be included in the right-hand side of the generalized variable bound

Parameters

scip	SCIP data structure
var	variable to check

Definition at line 368 of file prop_obbt.c.

static int getIterationsLeft	(	SCIP *	scip,
		SCIP_Longint	nolditerations,
		SCIP_Longint	itlimit
	)

static

returns number of LP iterations left (-1: no limit )

Parameters

scip	SCIP data structure
nolditerations	iterations count at the beginning of the corresponding function
itlimit	LP iteration limit (-1: no limit)

Definition at line 395 of file prop_obbt.c.

References Bound::boundtype, getFilterCoef(), MAX, MIN, NULL, SCIP_Real, SCIPdebugMessage, and SCIPgetNLPIterations().

static SCIP_Real getFilterCoef	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		SCIP_VAR *	var,
		SCIP_BOUNDTYPE	boundtype
	)

static

returns the objective coefficient for a variable's bound that will be chosen during filtering

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator
var	variable
boundtype	boundtype to be filtered?

Definition at line 425 of file prop_obbt.c.

Referenced by getIterationsLeft().

static SCIP_RETCODE createGenVBound	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		BOUND *	bound,
		SCIP_Bool *	found
	)

static

creates a genvbound if the dual LP solution provides such information

Consider the problem

min { +/- x_i : obj * x <= z, lb <= Ax <= ub, l <= x <= u },

where z is the current cutoff bound. Let (mu, nu, gamma, alpha, beta) >= 0 be the optimal solution of the dual of problem (P), where the variables correspond to the primal inequalities in the following way:

     Ax >=  lb    <->   mu
    -Ax >= -ub    <->   nu

-obj * x >= -z <-> gamma x >= l <-> alpha -x >= -u <-> beta

Fixing these multipliers, by weak duality, we obtain the inequality

+/- x_i >= lb*mu - ub*nu - z*gamma + l*alpha - u*beta

that holds for all primal feasible points x with objective value at least z. Setting

c = lb*mu - ub*nu, redcost_k = alpha_k - beta_k

we obtain the inequality

+/- x_i >= sum ( redcost_k * x_k ) + (-gamma) * cutoff_bound + c,

that holds for all primal feasible points with objective value at least cutoff_bound. Therefore, the latter inequality can be added as a generalized variable bound.

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator
bound	bound of x_i
found	pointer to store if we have found a non-trivial genvbound

Definition at line 499 of file prop_obbt.c.

Referenced by filterExistingLP().

static void exchangeBounds	(	SCIP_PROPDATA *	propdata,
		int	i
	)

static

exchange a bound which has been processed and updates the last undone and unfiltered bound index NOTE: this method has to be called after filtering or processing a bound

Parameters

propdata	propagator data
i	bound that was filtered or processed

Definition at line 671 of file prop_obbt.c.

References NULL.

Referenced by filterExistingLP().

static SCIP_RETCODE filterExistingLP	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		int *	nfiltered,
		BOUND *	currbound
	)

static

trying to filter some bounds using the existing LP solution

Parameters

scip	original SCIP data structure
propdata	data of the obbt propagator
nfiltered	how many bounds were filtered this round?
currbound	bound for which OBBT LP was solved (Note: might be NULL)

Definition at line 694 of file prop_obbt.c.

References Bound::boundtype, createGenVBound(), Bound::done, exchangeBounds(), Bound::filtered, filterRound(), Bound::found, NULL, SCIP_BASESTAT_BASIC, SCIP_Bool, SCIP_BOUNDTYPE_LOWER, SCIP_BOUNDTYPE_UPPER, SCIP_CALL, SCIP_OKAY, SCIP_Real, SCIPchgVarObjProbing(), SCIPcolGetBasisStatus(), SCIPdebugMessage, SCIPgetDepth(), SCIPgetNLPIterations(), SCIPgetNVars(), SCIPgetVarObjProbing(), SCIPgetVars(), SCIPinProbing(), SCIPisFeasGE(), SCIPisFeasLE(), SCIPisZero(), SCIPvarGetCol(), SCIPvarGetLbLocal(), SCIPvarGetLPSol(), SCIPvarGetName(), SCIPvarGetUbLocal(), setObjProbing(), solveLP(), TRUE, and Bound::var.

static SCIP_RETCODE filterRound	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		int	itlimit,
		int *	nfiltered,
		SCIP_Real *	objcoefs,
		int *	objcoefsinds,
		int	nobjcoefs
	)

static

enforces one round of filtering

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator
itlimit	LP iteration limit (-1: no limit)
nfiltered	how many bounds were filtered this round
objcoefs	array to store the nontrivial objective coefficients
objcoefsinds	array to store bound indices for which their corresponding variables has a nontrivial objective coefficient
nobjcoefs	number of nontrivial objective coefficients

Definition at line 810 of file prop_obbt.c.

Referenced by filterExistingLP().

static SCIP_RETCODE filterBounds	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		SCIP_Longint	itlimit
	)

static

filter some bounds that are not improvable by solving auxiliary LPs

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator
itlimit	LP iteration limit (-1: no limit)

Definition at line 971 of file prop_obbt.c.

static SCIP_RETCODE applyBoundChgs	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		SCIP_RESULT *	result
	)

static

applies possible bound changes that were found

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator
result	result pointer

Definition at line 1115 of file prop_obbt.c.

static SCIP_RETCODE tightenBoundProbing	(	SCIP *	scip,
		BOUND *	bound,
		SCIP_Real	newval,
		SCIP_Bool *	tightened
	)

static

tries to tighten a bound in probing mode

Parameters

scip	SCIP data structure
bound	bound that could be tightened
newval	new bound value
tightened	was tightening successful?

Definition at line 1182 of file prop_obbt.c.

static SCIP_DECL_SORTPTRCOMP ( compBoundsScore )

static

comparison method for two bounds w.r.t. their scores

Definition at line 1243 of file prop_obbt.c.

static SCIP_DECL_SORTPTRCOMP ( compBoundsBoundtype )

static

comparison method for two bounds w.r.t. their boundtype

Definition at line 1253 of file prop_obbt.c.

References NULL, SCIP_OKAY, SCIPdebugMessage, and SCIPsortDownPtr().

static SCIP_RETCODE sortBounds	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata
	)

static

sort the propdata->bounds array with their distance or their boundtype key

Parameters

scip	SCIP data structure
propdata	propagator data

Definition at line 1279 of file prop_obbt.c.

References Bound::boundtype, NULL, REALABS, SCIP_BOUNDTYPE_LOWER, SCIPvarGetLbLocal(), SCIPvarGetLPSol(), SCIPvarGetUbLocal(), and Bound::var.

static SCIP_Real evalBound	(	SCIP *	scip,
		BOUND *	bound
	)

static

evaluates a bound for the current LP solution

Definition at line 1295 of file prop_obbt.c.

References NULL, and SCIP_Real.

static int nextBound	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		SCIP_Bool	convexphase
	)

static

returns the index of the next undone and unfiltered bound with the smallest distance

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator
convexphase	consider only convex variables?

Definition at line 1311 of file prop_obbt.c.

static SCIP_RETCODE applySeparation	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		BOUND *	currbound,
		SCIP_Longint *	nleftiterations,
		SCIP_Bool *	success
	)

static

try to separate the solution of the last OBBT LP in order to learn better variable bounds; we apply additional separation rounds as long as the routine finds better bounds; because of dual degeneracy we apply a minimum number of separation rounds

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator
currbound	current bound
nleftiterations	number of left iterations (-1 for no limit)
success	pointer to store if we have found a better bound

Definition at line 1363 of file prop_obbt.c.

static SCIP_RETCODE findNewBounds	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		SCIP_Longint *	nleftiterations,
		SCIP_Bool	convexphase
	)

static

finds new variable bounds until no iterations left or all bounds have been checked

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator
nleftiterations	pointer to store the number of left iterations
convexphase	consider only convex variables?

Definition at line 1445 of file prop_obbt.c.

static SCIP_RETCODE applyObbt	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata,
		SCIP_Longint	itlimit,
		SCIP_RESULT *	result
	)

static

main function of obbt

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator
itlimit	LP iteration limit (-1: no limit)
result	result pointer

Definition at line 1684 of file prop_obbt.c.

Referenced by SCIP_DECL_PROPEXEC().

static unsigned int getScore	(	SCIP *	scip,
		BOUND *	bound,
		int	nlcount,
		int	maxnlcount
	)

static

computes the score of a bound

Parameters

scip	SCIP data structure
bound	pointer of bound
nlcount	number of nonlinear constraints containing the bounds variable
maxnlcount	maximal number of nonlinear constraints a variable appears in

Definition at line 1906 of file prop_obbt.c.

static SCIP_RETCODE countNLRowVarsNonConvexity	(	SCIP *	scip,
		int *	nlcounts,
		SCIP_NLROW *	nlrow
	)

static

count the variables which appear in non-convex term of nlrow

Parameters

scip	SCIP data structure
nlcounts	store the number each variable appears in a non-convex term
nlrow	nonlinear row

Definition at line 1949 of file prop_obbt.c.

static SCIP_RETCODE getNLPVarsNonConvexity	(	SCIP *	scip,
		int *	nlcounts
	)

static

count how often each variable appears in a non-convex term

Parameters

scip	SCIP data structure
nlcounts	store the number each variable appears in a non-convex term

Definition at line 2019 of file prop_obbt.c.

static SCIP_Bool varIsInteresting	(	SCIP *	scip,
		SCIP_VAR *	var,
		int	nlcount
	)

static

determines whether a variable is interesting

Parameters

scip	SCIP data structure
var	variable to check
nlcount	number of nonlinear constraints containing the variable or number of non-convex terms containing the variable (depends on propdata->onlynonconvexvars)

Definition at line 2161 of file prop_obbt.c.

static SCIP_RETCODE initBounds	(	SCIP *	scip,
		SCIP_PROPDATA *	propdata
	)

static

initializes interesting bounds

Parameters

scip	SCIP data structure
propdata	data of the obbt propagator

Definition at line 2177 of file prop_obbt.c.

Referenced by SCIP_DECL_PROPEXEC().

static SCIP_DECL_PROPINITSOL ( propInitsolObbt )

static

solving process initialization method of propagator (called when branch and bound process is about to begin)

Definition at line 2294 of file prop_obbt.c.

static SCIP_DECL_PROPEXEC ( propExecObbt )

static

execution method of propagator

Definition at line 2322 of file prop_obbt.c.

References applyObbt(), initBounds(), MAX, NULL, SCIP_CALL, SCIP_DECL_PROPEXITSOL(), SCIP_DECL_PROPRESPROP(), SCIP_DIDNOTFIND, SCIP_DIDNOTRUN, SCIP_Longint, SCIP_LPSOLSTAT_OPTIMAL, SCIP_LPSOLSTAT_UNBOUNDEDRAY, SCIP_OKAY, SCIPallColsInLP(), SCIPallowObjProp(), SCIPdebugMessage, SCIPgetCurrentNode(), SCIPgetDepth(), SCIPgetLPSolstat(), SCIPgetNRootLPIterations(), SCIPgetProbName(), SCIPinProbing(), SCIPnodeGetNumber(), and SCIPpropGetData().

static SCIP_DECL_PROPRESPROP ( propRespropObbt )

static

propagation conflict resolving method of propagator

Definition at line 2420 of file prop_obbt.c.

Referenced by SCIP_DECL_PROPEXEC().

static SCIP_DECL_PROPEXITSOL ( propExitsolObbt )

static

solving process deinitialization method of propagator (called before branch and bound process data is freed)

Definition at line 2429 of file prop_obbt.c.

Referenced by SCIP_DECL_PROPEXEC().

static SCIP_DECL_PROPFREE ( propFreeObbt )

static

destructor of propagator to free user data (called when SCIP is exiting)

Definition at line 2468 of file prop_obbt.c.

SCIP_RETCODE SCIPincludePropObbt ( SCIP * scip )

creates the obbt propagator and includes it in SCIP

Parameters

scip	SCIP data structure

Definition at line 2491 of file prop_obbt.c.

Referenced by SCIPincludeDefaultPlugins().

SCIP

Detailed Description

Macros

Typedefs

Functions

Macro Definition Documentation

Typedef Documentation

Function Documentation