Abstract base class for `objects'. More...

#include <OsiBranchingObject.hpp>

Inheritance diagram for OsiObject:

Public Member Functions
	OsiObject ()
	Default Constructor. More...

	OsiObject (const OsiObject &)
	Copy constructor. More...

OsiObject &	operator= (const OsiObject &rhs)
	Assignment operator. More...

virtual OsiObject *	clone () const =0
	Clone. More...

virtual	~OsiObject ()
	Destructor. More...

double	infeasibility (const OsiSolverInterface *solver, int &whichWay) const
	Infeasibility of the object. More...

virtual double	infeasibility (const OsiBranchingInformation *info, int &whichWay) const =0

virtual double	checkInfeasibility (const OsiBranchingInformation *info) const

virtual double	feasibleRegion (OsiSolverInterface *solver) const
	For the variable(s) referenced by the object, look at the current solution and set bounds to match the solution. More...

virtual double	feasibleRegion (OsiSolverInterface solver, const OsiBranchingInformation info) const =0
	For the variable(s) referenced by the object, look at the current solution and set bounds to match the solution. More...

virtual OsiBranchingObject *	createBranch (OsiSolverInterface , const OsiBranchingInformation , int) const
	Create a branching object and indicate which way to branch first. More...

virtual bool	canDoHeuristics () const
	Return true if object can take part in normal heuristics. More...

virtual bool	canMoveToNearest () const
	Return true if object can take part in move to nearest heuristic. More...

virtual int	columnNumber () const
	Column number if single column object -1 otherwise, Used by heuristics. More...

int	priority () const
	Return Priority - note 1 is highest priority. More...

void	setPriority (int priority)
	Set priority. More...

virtual bool	boundBranch () const
	Return true if branch should only bound variables. More...

virtual bool	canHandleShadowPrices () const
	Return true if knows how to deal with Pseudo Shadow Prices. More...

int	numberWays () const
	Return maximum number of ways branch may have. More...

void	setNumberWays (int numberWays)
	Set maximum number of ways branch may have. More...

void	setWhichWay (int way)
	Return preferred way to branch. More...

int	whichWay () const
	Return current preferred way to branch. More...

virtual int	preferredWay () const
	Get pre-emptive preferred way of branching - -1 off, 0 down, 1 up (for 2-way) More...

double	infeasibility () const
	Return infeasibility. More...

virtual double	upEstimate () const
	Return "up" estimate (default 1.0e-5) More...

virtual double	downEstimate () const
	Return "down" estimate (default 1.0e-5) More...

virtual void	resetBounds (const OsiSolverInterface *)
	Reset variable bounds to their original values. More...

virtual void	resetSequenceEtc (int, const int *)
	Change column numbers after preprocessing. More...

virtual void	updateBefore (const OsiObject *)
	Updates stuff like pseudocosts before threads. More...

virtual void	updateAfter (const OsiObject , const OsiObject )
	Updates stuff like pseudocosts after threads finished. More...

Protected Attributes
double	infeasibility_
	data More...

short	whichWay_
	Computed preferred way to branch. More...

short	numberWays_
	Maximum number of ways on branch. More...

int	priority_
	Priority. More...

Detailed Description

Abstract base class for `objects'.

The branching model used in Osi is based on the idea of an object. In the abstract, an object is something that has a feasible region, can be evaluated for infeasibility, can be branched on (i.e., there's some constructive action to be taken to move toward feasibility), and allows comparison of the effect of branching.

This class (OsiObject) is the base class for an object. To round out the branching model, the class OsiBranchingObject describes how to perform a branch, and the class OsiBranchDecision describes how to compare two OsiBranchingObjects.

To create a new type of object you need to provide three methods: infeasibility(), feasibleRegion(), and createBranch(), described below.

This base class is primarily virtual to allow for any form of structure. Any form of discontinuity is allowed.

As there is an overhead in getting information from solvers and because other useful information is available there is also an OsiBranchingInformation class which can contain pointers to information. If used it must at minimum contain pointers to current value of objective, maximum allowed objective and pointers to arrays for bounds and solution and direction of optimization. Also integer and primal tolerance.

Classes which inherit might have other information such as depth, number of solutions, pseudo-shadow prices etc etc. May be easier just to throw in here - as I keep doing

Definition at line 56 of file OsiBranchingObject.hpp.

Constructor & Destructor Documentation

OsiObject::OsiObject ( )

Default Constructor.

OsiObject::OsiObject ( const OsiObject & )

Copy constructor.

virtual OsiObject::~OsiObject ( )

virtual

Destructor.

Member Function Documentation

OsiObject& OsiObject::operator= ( const OsiObject & rhs )

Assignment operator.

virtual OsiObject* OsiObject::clone ( ) const

pure virtual

Clone.

Implemented in OsiLotsize, OsiSOS, and OsiSimpleInteger.

double OsiObject::infeasibility	(	const OsiSolverInterface *	solver,
		int &	whichWay
	)		const

Infeasibility of the object.

This is some measure of the infeasibility of the object. 0.0 indicates that the object is satisfied.

The preferred branching direction is returned in whichWay, where for normal two-way branching 0 is down, 1 is up

This is used to prepare for strong branching but should also think of case when no strong branching

The object may also compute an estimate of cost of going "up" or "down". This will probably be based on pseudo-cost ideas

This should also set mutable infeasibility_ and whichWay_ This is for instant re-use for speed

Default for this just calls infeasibility with OsiBranchingInformation NOTE - Convention says that an infeasibility of COIN_DBL_MAX means object has worked out it can't be satisfied!

virtual double OsiObject::infeasibility	(	const OsiBranchingInformation *	info,
		int &	whichWay
	)		const

pure virtual

Implemented in OsiLotsize, OsiSOS, and OsiSimpleInteger.

virtual double OsiObject::checkInfeasibility ( const OsiBranchingInformation * info ) const

virtual

virtual double OsiObject::feasibleRegion ( OsiSolverInterface * solver ) const

virtual

For the variable(s) referenced by the object, look at the current solution and set bounds to match the solution.

Returns measure of how much it had to move solution to make feasible

virtual double OsiObject::feasibleRegion	(	OsiSolverInterface *	solver,
		const OsiBranchingInformation *	info
	)		const

pure virtual

For the variable(s) referenced by the object, look at the current solution and set bounds to match the solution.

Returns measure of how much it had to move solution to make feasible Faster version

Implemented in OsiLotsize, OsiSOS, and OsiSimpleInteger.

virtual OsiBranchingObject* OsiObject::createBranch	(	OsiSolverInterface *	,
		const OsiBranchingInformation *	,
		int
	)		const

inlinevirtual

Create a branching object and indicate which way to branch first.

The branching object has to know how to create branches (fix variables, etc.)

Reimplemented in OsiLotsize, OsiSOS, and OsiSimpleInteger.

Definition at line 118 of file OsiBranchingObject.hpp.

virtual bool OsiObject::canDoHeuristics ( ) const

inlinevirtual

Return true if object can take part in normal heuristics.

Reimplemented in OsiLotsize, and OsiSOS.

Definition at line 128 of file OsiBranchingObject.hpp.

virtual bool OsiObject::canMoveToNearest ( ) const

inlinevirtual

Return true if object can take part in move to nearest heuristic.

Definition at line 134 of file OsiBranchingObject.hpp.

virtual int OsiObject::columnNumber ( ) const

virtual

Column number if single column object -1 otherwise, Used by heuristics.

Reimplemented in OsiLotsize, and OsiSimpleInteger.

int OsiObject::priority ( ) const

inline

Return Priority - note 1 is highest priority.

Definition at line 143 of file OsiBranchingObject.hpp.

void OsiObject::setPriority ( int priority )

inline

Set priority.

Definition at line 148 of file OsiBranchingObject.hpp.

virtual bool OsiObject::boundBranch ( ) const

inlinevirtual

Return true if branch should only bound variables.

Definition at line 154 of file OsiBranchingObject.hpp.

virtual bool OsiObject::canHandleShadowPrices ( ) const

inlinevirtual

Return true if knows how to deal with Pseudo Shadow Prices.

Reimplemented in OsiLotsize, OsiSOS, and OsiSimpleInteger.

Definition at line 159 of file OsiBranchingObject.hpp.

int OsiObject::numberWays ( ) const

inline

Return maximum number of ways branch may have.

Definition at line 164 of file OsiBranchingObject.hpp.

void OsiObject::setNumberWays ( int numberWays )

inline

Set maximum number of ways branch may have.

Definition at line 169 of file OsiBranchingObject.hpp.

void OsiObject::setWhichWay ( int way )

inline

Return preferred way to branch.

If two then way=0 means down and 1 means up, otherwise way points to preferred branch

Definition at line 177 of file OsiBranchingObject.hpp.

int OsiObject::whichWay ( ) const

inline

Return current preferred way to branch.

If two then way=0 means down and 1 means up, otherwise way points to preferred branch

Definition at line 185 of file OsiBranchingObject.hpp.

virtual int OsiObject::preferredWay ( ) const

inlinevirtual

Get pre-emptive preferred way of branching - -1 off, 0 down, 1 up (for 2-way)

Reimplemented in OsiObject2.

Definition at line 190 of file OsiBranchingObject.hpp.

double OsiObject::infeasibility ( ) const

inline

Return infeasibility.

Definition at line 195 of file OsiBranchingObject.hpp.

virtual double OsiObject::upEstimate ( ) const

virtual

Return "up" estimate (default 1.0e-5)

Reimplemented in OsiLotsize, OsiSOS, and OsiSimpleInteger.

virtual double OsiObject::downEstimate ( ) const

virtual

Return "down" estimate (default 1.0e-5)

Reimplemented in OsiLotsize, OsiSOS, and OsiSimpleInteger.

virtual void OsiObject::resetBounds ( const OsiSolverInterface * )

inlinevirtual

Reset variable bounds to their original values.

Bounds may be tightened, so it may be good to be able to reset them to their original values.

Reimplemented in OsiLotsize, and OsiSimpleInteger.

Definition at line 207 of file OsiBranchingObject.hpp.

virtual void OsiObject::resetSequenceEtc	(	int	,
		const int *
	)

inlinevirtual

Change column numbers after preprocessing.

Reimplemented in OsiLotsize, OsiSOS, and OsiSimpleInteger.

Definition at line 210 of file OsiBranchingObject.hpp.

virtual void OsiObject::updateBefore ( const OsiObject * )

inlinevirtual

Updates stuff like pseudocosts before threads.

Definition at line 212 of file OsiBranchingObject.hpp.

virtual void OsiObject::updateAfter	(	const OsiObject *	,
		const OsiObject *
	)

inlinevirtual

Updates stuff like pseudocosts after threads finished.

Definition at line 214 of file OsiBranchingObject.hpp.

Member Data Documentation

double OsiObject::infeasibility_

mutableprotected

data

Computed infeasibility

Definition at line 220 of file OsiBranchingObject.hpp.

short OsiObject::whichWay_

mutableprotected

Computed preferred way to branch.

Definition at line 222 of file OsiBranchingObject.hpp.

short OsiObject::numberWays_

protected

Maximum number of ways on branch.

Definition at line 224 of file OsiBranchingObject.hpp.

int OsiObject::priority_

protected

Priority.

Definition at line 226 of file OsiBranchingObject.hpp.

The documentation for this class was generated from the following file:

/tmp/DyLP-1.10.4/Osi/src/Osi/OsiBranchingObject.hpp

Public Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation