Interface between Abc and Cut Generation Library. More...

#include <AbcCutGenerator.h>

Collaboration diagram for AbcCutGenerator:

Public Member Functions
Generate Cuts
bool	generateCuts (OsiCuts &cs, bool fullScan)
	Generate cuts for the client model. More...

bool	generateCuts (OsiCuts &cs, bool fullScan)
	Generate cuts for the client model. More...

Constructors and destructors
	AbcCutGenerator ()
	Default constructor. More...

	AbcCutGenerator (AbcModel model, CglCutGenerator generator, int howOften=1, const char *name=NULL, bool normal=true, bool atSolution=false, bool infeasible=false)
	Normal constructor. More...

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

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

	~AbcCutGenerator ()
	Destructor. More...

	AbcCutGenerator ()
	Default constructor. More...

	AbcCutGenerator (AbcModel model, CglCutGenerator generator, int howOften=1, const char *name=NULL, bool normal=true, bool atSolution=false, bool infeasible=false)
	Normal constructor. More...

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

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

	~AbcCutGenerator ()
	Destructor. More...

Gets and sets
void	refreshModel (AbcModel *model)
	Set the client model. More...

const char *	cutGeneratorName () const
	return name of generator More...

void	setHowOften (int value)
	Set the cut generation interval. More...

int	howOften () const
	Get the cut generation interval. More...

bool	normal () const
	Get whether the cut generator should be called in the normal place. More...

void	setNormal (bool value)
	Set whether the cut generator should be called in the normal place. More...

bool	atSolution () const
	Get whether the cut generator should be called when a solution is found. More...

void	setAtSolution (bool value)
	Set whether the cut generator should be called when a solution is found. More...

bool	whenInfeasible () const
	Get whether the cut generator should be called when the subproblem is found to be infeasible. More...

void	setWhenInfeasible (bool value)
	Set whether the cut generator should be called when the subproblem is found to be infeasible. More...

CglCutGenerator *	generator () const
	Get the `CglCutGenerator` bound to this `AbcCutGenerator`. More...

void	refreshModel (AbcModel *model)
	Set the client model. More...

const char *	cutGeneratorName () const
	return name of generator More...

void	setHowOften (int value)
	Set the cut generation interval. More...

int	howOften () const
	Get the cut generation interval. More...

bool	normal () const
	Get whether the cut generator should be called in the normal place. More...

void	setNormal (bool value)
	Set whether the cut generator should be called in the normal place. More...

bool	atSolution () const
	Get whether the cut generator should be called when a solution is found. More...

void	setAtSolution (bool value)
	Set whether the cut generator should be called when a solution is found. More...

bool	whenInfeasible () const
	Get whether the cut generator should be called when the subproblem is found to be infeasible. More...

void	setWhenInfeasible (bool value)
	Set whether the cut generator should be called when the subproblem is found to be infeasible. More...

CglCutGenerator *	generator () const
	Get the `CglCutGenerator` bound to this `AbcCutGenerator`. More...

Private Attributes
AbcModel *	model_
	The client model. More...

CglCutGenerator *	generator_

int	whenCutGenerator_
	Number of nodes between calls to the CglCutGenerator::generateCuts routine. More...

char *	generatorName_
	Name of generator. More...

bool	normal_
	Whether to call the generator in the normal place. More...

bool	atSolution_
	Whether to call the generator when a new solution is found. More...

bool	whenInfeasible_
	Whether to call generator when a subproblem is found to be infeasible. More...

Detailed Description

Interface between Abc and Cut Generation Library.

AbcCutGenerator is intended to provide an intelligent interface between Abc and the cutting plane algorithms in the CGL. A AbcCutGenerator is bound to a CglCutGenerator and to an AbcModel. It contains parameters which control when and how the generateCuts method of the CglCutGenerator will be called.

The builtin decision criteria available to use when deciding whether to generate cuts are limited: every X nodes, when a solution is found, and when a subproblem is found to be infeasible. The idea is that the class will grow more intelligent with time.

Todo:: Add a pointer to function member which will allow a client to install their own decision algorithm to decide whether or not to call the CGL generateCuts method. Create a default decision method that looks at the builtin criteria.

Todo:: It strikes me as not good that generateCuts contains code specific to individual CGL algorithms. Another set of pointer to function members, so that the client can specify the cut generation method as well as pre- and post-generation methods? Taken a bit further, should this class contain a bunch of pointer to function members, one for each of the places where the cut generator might be referenced? Initialization, root node, search tree node, discovery of solution, and termination all come to mind. Initialization and termination would also be useful for instrumenting sbb.

AbcCutGenerator is intended to provide an intelligent interface between Abc and the cutting plane algorithms in the CGL. A AbcCutGenerator is bound to a CglCutGenerator and to an AbcModel. It contains parameters which control when and how the generateCuts method of the CglCutGenerator will be called.

The builtin decision criteria available to use when deciding whether to generate cuts are limited: every X nodes, when a solution is found, and when a subproblem is found to be infeasible. The idea is that the class will grow more intelligent with time.

Todo:: Add a pointer to function member which will allow a client to install their own decision algorithm to decide whether or not to call the CGL generateCuts method. Create a default decision method that looks at the builtin criteria.

Todo:: It strikes me as not good that generateCuts contains code specific to individual CGL algorithms. Another set of pointer to function members, so that the client can specify the cut generation method as well as pre- and post-generation methods? Taken a bit further, should this class contain a bunch of pointer to function members, one for each of the places where the cut generator might be referenced? Initialization, root node, search tree node, discovery of solution, and termination all come to mind. Initialization and termination would also be useful for instrumenting sbb.

Definition at line 69 of file AbcCutGenerator.h.

Constructor & Destructor Documentation

AbcCutGenerator::AbcCutGenerator ( )

Default constructor.

AbcCutGenerator::AbcCutGenerator	(	AbcModel *	model,
		CglCutGenerator *	generator,
		int	howOften = `1`,
		const char *	name = `NULL`,
		bool	normal = `true`,
		bool	atSolution = `false`,
		bool	infeasible = `false`
	)

Normal constructor.

AbcCutGenerator::AbcCutGenerator ( const AbcCutGenerator & )

Copy constructor.

AbcCutGenerator::~AbcCutGenerator ( )

Destructor.

AbcCutGenerator::AbcCutGenerator ( )

Default constructor.

AbcCutGenerator::AbcCutGenerator	(	AbcModel *	model,
		CglCutGenerator *	generator,
		int	howOften = `1`,
		const char *	name = `NULL`,
		bool	normal = `true`,
		bool	atSolution = `false`,
		bool	infeasible = `false`
	)

Normal constructor.

AbcCutGenerator::AbcCutGenerator ( const AbcCutGenerator & )

Copy constructor.

AbcCutGenerator::~AbcCutGenerator ( )

Destructor.

Member Function Documentation

bool AbcCutGenerator::generateCuts	(	OsiCuts &	cs,
		bool	fullScan
	)

Generate cuts for the client model.

Evaluate the state of the client model and decide whether to generate cuts. The generated cuts are inserted into and returned in the collection of cuts cs.

If fullScan is true, the generator is obliged to call the CGL generateCuts routine. Otherwise, it is free to make a local decision. The current implementation uses whenCutGenerator_ to decide.

The routine returns true if reoptimisation is needed (because the state of the solver interface has been modified).

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

Assignment operator.

void AbcCutGenerator::refreshModel ( AbcModel * model )

Set the client model.

In addition to setting the client model, refreshModel also calls the refreshSolver method of the CglCutGenerator object.

const char* AbcCutGenerator::cutGeneratorName ( ) const

inline

return name of generator

Definition at line 124 of file AbcCutGenerator.h.

References generatorName_.

void AbcCutGenerator::setHowOften ( int value )

Set the cut generation interval.

Set the number of nodes evaluated between calls to the Cgl object's generateCuts routine.

If value is positive, cuts will always be generated at the specified interval. If value is negative, cuts will initially be generated at the specified interval, but Abc may adjust the value depending on the success of cuts produced by this generator.

A value of -100 disables the generator, while a value of -99 means just at root.

int AbcCutGenerator::howOften ( ) const

inline

Get the cut generation interval.

Definition at line 146 of file AbcCutGenerator.h.

References whenCutGenerator_.

bool AbcCutGenerator::normal ( ) const

inline

Get whether the cut generator should be called in the normal place.

Definition at line 150 of file AbcCutGenerator.h.

References normal_.

void AbcCutGenerator::setNormal ( bool value )

inline

Set whether the cut generator should be called in the normal place.

Definition at line 153 of file AbcCutGenerator.h.

References normal_.

bool AbcCutGenerator::atSolution ( ) const

inline

Get whether the cut generator should be called when a solution is found.

Definition at line 156 of file AbcCutGenerator.h.

References atSolution_.

void AbcCutGenerator::setAtSolution ( bool value )

inline

Set whether the cut generator should be called when a solution is found.

Definition at line 159 of file AbcCutGenerator.h.

References atSolution_.

bool AbcCutGenerator::whenInfeasible ( ) const

inline

Get whether the cut generator should be called when the subproblem is

found to be infeasible.

Definition at line 164 of file AbcCutGenerator.h.

References whenInfeasible_.

void AbcCutGenerator::setWhenInfeasible ( bool value )

inline

Set whether the cut generator should be called when the subproblem is

found to be infeasible.

Definition at line 169 of file AbcCutGenerator.h.

References whenInfeasible_.

CglCutGenerator* AbcCutGenerator::generator ( ) const

inline

Get the CglCutGenerator bound to this AbcCutGenerator.

Definition at line 172 of file AbcCutGenerator.h.

References generator_.

bool AbcCutGenerator::generateCuts	(	OsiCuts &	cs,
		bool	fullScan
	)

Generate cuts for the client model.

Evaluate the state of the client model and decide whether to generate cuts. The generated cuts are inserted into and returned in the collection of cuts cs.

If fullScan is true, the generator is obliged to call the CGL generateCuts routine. Otherwise, it is free to make a local decision. The current implementation uses whenCutGenerator_ to decide.

The routine returns true if reoptimisation is needed (because the state of the solver interface has been modified).

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

Assignment operator.

void AbcCutGenerator::refreshModel ( AbcModel * model )

Set the client model.

In addition to setting the client model, refreshModel also calls the refreshSolver method of the CglCutGenerator object.

const char* AbcCutGenerator::cutGeneratorName ( ) const

inline

return name of generator

Definition at line 124 of file AbcCutGenerator.h.

References generatorName_.

void AbcCutGenerator::setHowOften ( int value )

Set the cut generation interval.

Set the number of nodes evaluated between calls to the Cgl object's generateCuts routine.

If value is positive, cuts will always be generated at the specified interval. If value is negative, cuts will initially be generated at the specified interval, but Abc may adjust the value depending on the success of cuts produced by this generator.

A value of -100 disables the generator, while a value of -99 means just at root.

int AbcCutGenerator::howOften ( ) const

inline

Get the cut generation interval.

Definition at line 146 of file AbcCutGenerator.h.

References whenCutGenerator_.

bool AbcCutGenerator::normal ( ) const

inline

Get whether the cut generator should be called in the normal place.

Definition at line 150 of file AbcCutGenerator.h.

References normal_.

void AbcCutGenerator::setNormal ( bool value )

inline

Set whether the cut generator should be called in the normal place.

Definition at line 153 of file AbcCutGenerator.h.

References normal_.

bool AbcCutGenerator::atSolution ( ) const

inline

Get whether the cut generator should be called when a solution is found.

Definition at line 156 of file AbcCutGenerator.h.

References atSolution_.

void AbcCutGenerator::setAtSolution ( bool value )

inline

Set whether the cut generator should be called when a solution is found.

Definition at line 159 of file AbcCutGenerator.h.

References atSolution_.

bool AbcCutGenerator::whenInfeasible ( ) const

inline

Get whether the cut generator should be called when the subproblem is

found to be infeasible.

Definition at line 164 of file AbcCutGenerator.h.

References whenInfeasible_.

void AbcCutGenerator::setWhenInfeasible ( bool value )

inline

Set whether the cut generator should be called when the subproblem is

found to be infeasible.

Definition at line 169 of file AbcCutGenerator.h.

References whenInfeasible_.

CglCutGenerator* AbcCutGenerator::generator ( ) const

inline

Get the CglCutGenerator bound to this AbcCutGenerator.

Definition at line 172 of file AbcCutGenerator.h.

References generator_.

Member Data Documentation

AbcModel * AbcCutGenerator::model_

private

The client model.

Definition at line 178 of file AbcCutGenerator.h.

CglCutGenerator * AbcCutGenerator::generator_

private

Definition at line 181 of file AbcCutGenerator.h.

Referenced by generator().

int AbcCutGenerator::whenCutGenerator_

private

Number of nodes between calls to the CglCutGenerator::generateCuts

routine.

Definition at line 186 of file AbcCutGenerator.h.

Referenced by howOften().

char * AbcCutGenerator::generatorName_

private

Name of generator.

Definition at line 189 of file AbcCutGenerator.h.

Referenced by cutGeneratorName().

bool AbcCutGenerator::normal_

private

Whether to call the generator in the normal place.

Definition at line 192 of file AbcCutGenerator.h.

Referenced by normal(), and setNormal().

bool AbcCutGenerator::atSolution_

private

Whether to call the generator when a new solution is found.

Definition at line 195 of file AbcCutGenerator.h.

Referenced by atSolution(), and setAtSolution().

bool AbcCutGenerator::whenInfeasible_

private

Whether to call generator when a subproblem is found to be infeasible.

Definition at line 198 of file AbcCutGenerator.h.

Referenced by setWhenInfeasible(), and whenInfeasible().

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

/tmp/Dip-0.92.4/Alps/examples/Abc/AbcCutGenerator.h
/tmp/Dip-0.92.4/Alps/test/AbcCutGenerator.h

Public Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation