NOX::LineSearch::FullStep Class Reference

Simplest line search - always take the full step. More...

#include <NOX_LineSearch_FullStep.H>

Inheritance diagram for NOX::LineSearch::FullStep:

Collaboration diagram for NOX::LineSearch::FullStep:

List of all members.

Public Member Functions

FullStep (const Teuchos::RCP< NOX::GlobalData > &gd, Teuchos::ParameterList &params)

Constructor.

~FullStep ()

Destructor.

bool reset (const Teuchos::RCP< NOX::GlobalData > &gd, Teuchos::ParameterList &params)

bool compute (NOX::Abstract::Group &newgrp, double &step, const NOX::Abstract::Vector &dir, const NOX::Solver::Generic &s)

Perform a line search.

Private Attributes

double stepSize

Full step length.

Detailed Description

Simplest line search - always take the full step.

This line search can be called via NOX::LineSearch::Manager.

The following parameters can be specified in the "Full Step" sublist of the "Line Search" sublist:

"Full Step" - length of a full step (defaults to 1.0)

Definition at line 60 of file NOX_LineSearch_FullStep.H.

Constructor & Destructor Documentation

FullStep::FullStep	(	const Teuchos::RCP< NOX::GlobalData > &	gd,
		Teuchos::ParameterList &	params
	)

Constructor.

Definition at line 54 of file NOX_LineSearch_FullStep.C.

References stepSize.

FullStep::~FullStep ( )

Destructor.

Definition at line 61 of file NOX_LineSearch_FullStep.C.

Member Function Documentation

bool FullStep::compute	(	NOX::Abstract::Group &	grp,
		double &	step,
		const NOX::Abstract::Vector &	dir,
		const NOX::Solver::Generic &	s
	)			`[virtual]`

Perform a line search.

On input:

Parameters:

	grp	The initial solution vector, $x_{\rm old}$ .
	dir	A vector of directions to be used in the line search, .
	s	The nonlinear solver.

On output:

Parameters:

	step	The distance the direction was scaled, $\lambda$ .
	grp	The `grp` is updated with a new solution, $x_{\rm new}$ , resulting from the linesearch. Normally, for a single direction line search, this is computed as:

$x_{\rm new} = x_{\rm old} + \lambda d.$

Ideally, $\|F(x_{\rm new})\| < \|F(x_{\rm old})\|$ (e.g the final direction is a descent direction).

Note that the dir object is a std::vector. For typical line searches as described in the above equation, this vector is of size one. We have used a std::vector to allow for special cases of multi-directional line searches such as the Bader/Schnabel curvillinear line search.

Return value is true for a successful line search computation.

Implements NOX::LineSearch::Generic.

Definition at line 74 of file NOX_LineSearch_FullStep.C.

References NOX::Abstract::Group::computeX(), NOX::Solver::Generic::getPreviousSolutionGroup(), and stepSize.

Member Data Documentation

double NOX::LineSearch::FullStep::stepSize [private]

Full step length.

Definition at line 82 of file NOX_LineSearch_FullStep.H.

Referenced by compute(), and FullStep().

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


Public Member Functions
	FullStep (const Teuchos::RCP< NOX::GlobalData > &gd, Teuchos::ParameterList &params)
	Constructor.
	~FullStep ()
	Destructor.
bool	reset (const Teuchos::RCP< NOX::GlobalData > &gd, Teuchos::ParameterList &params)
bool	compute (NOX::Abstract::Group &newgrp, double &step, const NOX::Abstract::Vector &dir, const NOX::Solver::Generic &s)
	Perform a line search.
Private Attributes
double	stepSize
	Full step length.