ibex::BoxNarrow Class Reference
[Contractors]

Box narrowing contractor. More...

#include <IbexBoxNarrow.h>

Inheritance diagram for ibex::BoxNarrow:

List of all members.

Public Member Functions
	BoxNarrow (const Equality &equ, Space &space, REAL var_ratio=default_var_ratio, REAL w_newton=UnivNewton::default_precision)
	BoxNarrow (const BoxNarrow &b)
	~BoxNarrow ()
void	narrow (int var)
virtual void	contract ()
virtual bool	involves (int ent) const
virtual BoxNarrow *	copy () const
virtual void	accept_printer (const OperatorPrinter &p) const
Public Attributes
const REAL	var_ratio
const Equality &	equ
Static Public Attributes
static const REAL	default_var_ratio = __IBEX_DEFAULT_BOX_VAR_RATIO

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Detailed Description

Box narrowing contractor.

A contraction obtained with a dichotomic application of the univariate Newton iteration. This atomic contractor is mainly used by the box contractor.

See also:

ibex::UnivNewton.

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Constructor & Destructor Documentation

ibex::BoxNarrow::BoxNarrow	(	const Equality &	equ,
		Space &	space,
		REAL	var_ratio = default_var_ratio,
		REAL	w_newton = UnivNewton::default_precision
	)

Build a box narrowing contractor.

Parameters:

	equ	- The equality to build this contractor with.
	space	- The space
	var_ratio	- Minimum width of a slice in the narrow procedure (the slice width must not be greater that var_ratio times the initial diameter of the domain). Default value is default_var_ratio.
	w_newton	- Criterion for stopping the interval univariate Newton iteration used to contract a slice. If a step of interval univariate Newton does not reduce the variable domain diameter by more than w_newton (this is not ratio but an absolute value), then the procedure stops. Default value is ibex::UnivNewton::default_precision.

ibex::BoxNarrow::BoxNarrow

(

const BoxNarrow &

b

)

Duplicate this instance.

ibex::BoxNarrow::~BoxNarrow

(

)

Delete this instance.

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Member Function Documentation

void ibex::BoxNarrow::narrow

(

int

var

)

Apply narrowing on a variable var.

Exceptions:

UnfeasibilityException

- if inconsisteny is detected.

void ibex::BoxNarrow::contract

(

)

[virtual]

Appliy generic contraction.

The indicators structure should contain a specific scope value. This value being the variable onto which narrowing has to be enforced. The procedure also takes into account the impact if it is set to NO_VAR (improving efficiency).

Remarks:

if indicators are not specified or if scope is set to ALL_VARS, all the variables are narrowed successively (although not forbidden, a call to this method is likely to be a mistake).

See also:

ibex::Contractor::contract(const Indicators&).

Implements ibex::Contractor.

virtual bool ibex::BoxNarrow::involves

(

int

ent

)

const [inline, virtual]

Return true if the entity ent is involved in the expression of this equation.

Reimplemented from ibex::Contractor.

virtual BoxNarrow* ibex::BoxNarrow::copy

(

)

const [inline, virtual]

Implement the contractor abstract copy.

Implements ibex::Contractor.

virtual void ibex::BoxNarrow::accept_printer

(

const OperatorPrinter &

p

)

const [inline, virtual]

Accept the pretty printer.

Reimplemented from ibex::Operator.

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Member Data Documentation

const REAL ibex::BoxNarrow::var_ratio

Variable splitting ratio. Set by default to default_var_ratio.

const REAL ibex::BoxNarrow::default_var_ratio = __IBEX_DEFAULT_BOX_VAR_RATIO [static]

Default variable splitting ratio. Set to 0.03.

const Equality& ibex::BoxNarrow::equ

The equation

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

• src/IbexBoxNarrow.h
• src/IbexBoxNarrow.cpp