math_FRPR Class Reference

this class implements the Fletcher-Reeves-Polak_Ribiere minimization algorithm of a function of multiple variables. Knowledge of the function's gradient is required. More...

`#include <math_FRPR.hxx>`

## Public Member Functions

math_FRPR (const math_MultipleVarFunctionWithGradient &theFunction, const Standard_Real theTolerance, const Standard_Integer theNbIterations=200, const Standard_Real theZEPS=1.0e-12)
Initializes the computation of the minimum of F. Warning: constructor does not perform computations. More...

virtual ~math_FRPR ()
Destructor. More...

void Perform (math_MultipleVarFunctionWithGradient &theFunction, const math_Vector &theStartingPoint)
The solution F = Fi is found when 2.0 * abs(Fi - Fi-1) <= Tolerance * (abs(Fi) + abs(Fi-1) + ZEPS). More...

The solution F = Fi is found when: 2.0 * abs(Fi - Fi-1) <= Tolerance * (abs(Fi) + abs(Fi-1)) + ZEPS. The maximum number of iterations allowed is given by NbIterations. More...

Standard_Boolean IsDone () const
Returns true if the computations are successful, otherwise returns false. More...

const math_VectorLocation () const
returns the location vector of the minimum. Exception NotDone is raised if the minimum was not found. More...

void Location (math_Vector &Loc) const
outputs the location vector of the minimum in Loc. Exception NotDone is raised if the minimum was not found. Exception DimensionError is raised if the range of Loc is not equal to the range of the StartingPoint. More...

Standard_Real Minimum () const
returns the value of the minimum. Exception NotDone is raised if the minimum was not found. More...

returns the gradient vector at the minimum. Exception NotDone is raised if the minimum was not found. More...

outputs the gradient vector at the minimum in Grad. Exception NotDone is raised if the minimum was not found. Exception DimensionError is raised if the range of Grad is not equal to the range of the StartingPoint. More...

Standard_Integer NbIterations () const
returns the number of iterations really done during the computation of the minimum. Exception NotDone is raised if the minimum was not found. More...

void Dump (Standard_OStream &o) const
Prints on the stream o information on the current state of the object. Is used to redefine the operator <<. More...

## Protected Attributes

math_Vector TheLocation

Standard_Real TheMinimum

Standard_Real PreviousMinimum

Standard_Real XTol

Standard_Real EPSZ

## Detailed Description

this class implements the Fletcher-Reeves-Polak_Ribiere minimization algorithm of a function of multiple variables. Knowledge of the function's gradient is required.

## Constructor & Destructor Documentation

 math_FRPR::math_FRPR ( const math_MultipleVarFunctionWithGradient & theFunction, const Standard_Real theTolerance, const Standard_Integer theNbIterations = `200`, const Standard_Real theZEPS = `1.0e-12` )

Initializes the computation of the minimum of F. Warning: constructor does not perform computations.

 virtual math_FRPR::~math_FRPR ( )
virtual

Destructor.

## Member Function Documentation

 void math_FRPR::Dump ( Standard_OStream & o ) const

Prints on the stream o information on the current state of the object. Is used to redefine the operator <<.

 const math_Vector& math_FRPR::Gradient ( ) const

returns the gradient vector at the minimum. Exception NotDone is raised if the minimum was not found.

outputs the gradient vector at the minimum in Grad. Exception NotDone is raised if the minimum was not found. Exception DimensionError is raised if the range of Grad is not equal to the range of the StartingPoint.

 Standard_Boolean math_FRPR::IsDone ( ) const

Returns true if the computations are successful, otherwise returns false.

 virtual Standard_Boolean math_FRPR::IsSolutionReached ( math_MultipleVarFunctionWithGradient & theFunction )
virtual

The solution F = Fi is found when: 2.0 * abs(Fi - Fi-1) <= Tolerance * (abs(Fi) + abs(Fi-1)) + ZEPS. The maximum number of iterations allowed is given by NbIterations.

 const math_Vector& math_FRPR::Location ( ) const

returns the location vector of the minimum. Exception NotDone is raised if the minimum was not found.

 void math_FRPR::Location ( math_Vector & Loc ) const

outputs the location vector of the minimum in Loc. Exception NotDone is raised if the minimum was not found. Exception DimensionError is raised if the range of Loc is not equal to the range of the StartingPoint.

 Standard_Real math_FRPR::Minimum ( ) const

returns the value of the minimum. Exception NotDone is raised if the minimum was not found.

 Standard_Integer math_FRPR::NbIterations ( ) const

returns the number of iterations really done during the computation of the minimum. Exception NotDone is raised if the minimum was not found.

 void math_FRPR::Perform ( math_MultipleVarFunctionWithGradient & theFunction, const math_Vector & theStartingPoint )

The solution F = Fi is found when 2.0 * abs(Fi - Fi-1) <= Tolerance * (abs(Fi) + abs(Fi-1) + ZEPS).

## Field Documentation

 Standard_Real math_FRPR::EPSZ
protected
 Standard_Real math_FRPR::PreviousMinimum
protected