NOX::LineSearch::Generic Class Reference

Base class line search interface. More...

#include <NOX_LineSearch_Generic.H>

Inheritance diagram for NOX::LineSearch::Generic:

Inheritance graph
[legend]

List of all members.

Public Member Functions

 Generic ()
 Default constructor.
virtual ~Generic ()
 Destructor.
virtual bool compute (NOX::Abstract::Group &grp, double &step, const NOX::Abstract::Vector &dir, const NOX::Solver::Generic &s)=0
 Perform a line search.


Detailed Description

Base class line search interface.

Every line search should respect the following Parameter:

Definition at line 73 of file NOX_LineSearch_Generic.H.


Constructor & Destructor Documentation

NOX::LineSearch::Generic::Generic (  )  [inline]

Default constructor.

Definition at line 78 of file NOX_LineSearch_Generic.H.

virtual NOX::LineSearch::Generic::~Generic (  )  [inline, virtual]

Destructor.

Definition at line 81 of file NOX_LineSearch_Generic.H.


Member Function Documentation

virtual bool NOX::LineSearch::Generic::compute ( NOX::Abstract::Group grp,
double &  step,
const NOX::Abstract::Vector dir,
const NOX::Solver::Generic s 
) [pure 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, $d$.
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.

Implemented in NOX::LineSearch::Backtrack, NOX::LineSearch::FullStep, NOX::LineSearch::MoreThuente, NOX::LineSearch::NonlinearCG, and NOX::LineSearch::Polynomial.


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

Generated on Wed Oct 21 14:28:47 2009 for Nonlinear Solver Project by  doxygen 1.5.9