MultiGrid< T > Class Template Reference

#include <MultiGrid.H>

Inheritance diagram for MultiGrid< T >:

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Collaboration diagram for MultiGrid< T >:

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List of all members.

Detailed Description

template<class T>
class MultiGrid< T >

Class to execute geometric multigrid. This class is not meant to be particularly user-friendly and a good option for people who want something a tad less raw is to use AMRMultiGrid instead.


Public Member Functions
	MultiGrid ()
virtual	~MultiGrid ()
virtual void	define (MGLevelOpFactory< T > &a_factory, LinearSolver< T > *a_bottomSolver, const ProblemDomain &a_domain, int a_maxDepth=-1)
	Function to define a MultiGrid object.
virtual void	solve (T &a_phi, const T &a_rhs, Real a_tolerance, int a_maxIterations, int verbosity=0)
virtual void	oneCycle (T &a_e, const T &a_res)
	Execute ONE v-cycle of multigrid.
void	init (const T &a_correction, const T &a_residual)
void	cycle (int a_depth, T &a_correction, const T &a_residual)
void	clear ()
void	setBottomSolver (LinearSolver< T > *a_bottomSolver)
Vector< MGLevelOp< T > * >	getAllOperators ()
Public Attributes
int	m_depth
int	m_defaultDepth
int	m_pre
int	m_post
int	m_bottom
int	m_cycle
int	m_numMG
bool	m_homogeneous
LinearSolver< T > *	m_bottomSolver
Protected Attributes
bool	m_defined
int	m_bottomCells
ProblemDomain	m_topLevelDomain
Vector< MGLevelOp< T > * >	m_op
Vector< T * >	m_residual
Vector< T * >	m_correction
Private Member Functions
	MultiGrid (const MultiGrid< T > &a_opin)
void	operator= (const MultiGrid< T > &a_opin)

Constructor & Destructor Documentation

template<class T>

MultiGrid< T >::MultiGrid ( ) [inline]

template<class T>

MultiGrid< T >::~MultiGrid ( ) [inline, virtual]

References MultiGrid< T >::clear().

template<class T>

MultiGrid< T >::MultiGrid ( const MultiGrid< T > & a_opin ) [inline, private]

Member Function Documentation

template<class T>

void MultiGrid< T >::define	(	MGLevelOpFactory< T > &	a_factory,
		LinearSolver< T > *	a_bottomSolver,
		const ProblemDomain &	a_domain,
		int	a_maxDepth = `-1`
	)			`[inline, virtual]`

Function to define a MultiGrid object.

a_factory is the factory for generating operators. a_bottomSolver is called at the bottom of v-cycle. a_domain is the problem domain at the top of the vcycle. maxDepth defines the location of the bottom of the v-cycle. The vycle will terminate (hit bottom) when the factory returns NULL for a paticular depth if maxdepth = -1. Otherwise the vycle terminates at maxdepth.

References CH_SPACEDIM, CH_TIME, ProblemDomain::domainBox(), i, MultiGrid< T >::m_bottomCells, MultiGrid< T >::m_bottomSolver, MultiGrid< T >::m_correction, MultiGrid< T >::m_defaultDepth, MultiGrid< T >::m_defined, MultiGrid< T >::m_depth, MultiGrid< T >::m_op, MultiGrid< T >::m_residual, MultiGrid< T >::m_topLevelDomain, MGLevelOpFactory< T >::MGnewOp(), Box::numPts(), Vector< T >::push_back(), and Vector< T >::resize().

template<class T>

void MultiGrid< T >::solve	(	T &	a_phi,
		const T &	a_rhs,
		Real	a_tolerance,
		int	a_maxIterations,
		int	verbosity = `0`
	)			`[inline, virtual]`

solve L(a_phi) = a_rhs. Tolerance is how much you want the norm of the error reduced. verbosity is how chatty you want the function to be. maxIterations is the maximum number of v-cycles. This does the whole residual correction switcharoo and calls oneCycle up to maxIterations times, evaluating the residual as it goes.

References CH_TIME, Vector< T >::clear(), MultiGrid< T >::cycle(), MultiGrid< T >::init(), MultiGrid< T >::m_op, Max(), and pout().

template<class T>

void MultiGrid< T >::oneCycle	(	T &	a_e,
		const T &	a_res
	)			`[inline, virtual]`

Execute ONE v-cycle of multigrid.

If you want the solution to converge, you need to iterate this. See solve() or AMRMultiGrid::solve for a more automatic solve() function. This operates residual-correction form of solution so all boundary conditions are assumed to be homogeneous. L(a_e) = a_res

References Vector< T >::clear(), MultiGrid< T >::cycle(), MultiGrid< T >::m_homogeneous, and MultiGrid< T >::m_op.

template<class T>

void MultiGrid< T >::init	(	const T &	a_correction,
		const T &	a_residual
	)			`[inline]`

References CH_TIME, i, MultiGrid< T >::m_correction, MultiGrid< T >::m_depth, MultiGrid< T >::m_op, and MultiGrid< T >::m_residual.

Referenced by MultiGrid< T >::solve().

template<class T>

void MultiGrid< T >::cycle	(	int	a_depth,
		T &	a_correction,
		const T &	a_residual
	)			`[inline]`

References MultiGrid< T >::m_bottom, MultiGrid< T >::m_bottomCells, MultiGrid< T >::m_bottomSolver, MultiGrid< T >::m_correction, MultiGrid< T >::m_cycle, MultiGrid< T >::m_depth, MultiGrid< T >::m_op, MultiGrid< T >::m_post, MultiGrid< T >::m_pre, and MultiGrid< T >::m_residual.

Referenced by MultiGrid< T >::oneCycle(), and MultiGrid< T >::solve().

template<class T>

void MultiGrid< T >::clear ( ) [inline]

References i, MultiGrid< T >::m_correction, MultiGrid< T >::m_defined, MultiGrid< T >::m_op, MultiGrid< T >::m_residual, Vector< T >::resize(), and Vector< T >::size().

Referenced by MultiGrid< T >::~MultiGrid().

template<class T>

void MultiGrid< T >::setBottomSolver ( LinearSolver< T > * a_bottomSolver ) [inline]

References MultiGrid< T >::m_bottomSolver, MultiGrid< T >::m_depth, and MultiGrid< T >::m_op.

template<class T>

Vector< MGLevelOp< T > * > MultiGrid< T >::getAllOperators ( ) [inline]

for changing coefficients --- not for the faint of heart.

References MultiGrid< T >::m_op.

template<class T>

void MultiGrid< T >::operator= ( const MultiGrid< T > & a_opin ) [inline, private]

Member Data Documentation

template<class T>

int MultiGrid< T >::m_depth

Public solver parameters. m_pre and m_post are the ones that usually get set and are the number of relaxations performed before and after multigrid recursion. See AMRMultiGrid for a more user-friendly interface.

Referenced by MultiGrid< T >::cycle(), MultiGrid< T >::define(), MultiGrid< T >::init(), and MultiGrid< T >::setBottomSolver().

template<class T>

int MultiGrid< T >::m_defaultDepth

Referenced by MultiGrid< T >::define().

template<class T>

int MultiGrid< T >::m_pre

Referenced by MultiGrid< T >::cycle().

template<class T>

int MultiGrid< T >::m_post

Referenced by MultiGrid< T >::cycle().

template<class T>

int MultiGrid< T >::m_bottom