#include <MultiGrid.H>

Inheritance diagram for MultiGrid< T >:

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, MGLevelOp< T > a_finestLevelOp=NULL)
	Function to define a MultiGrid object. More...

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. More...

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

ProblemDomain	m_topLevelDomain

Protected Attributes
bool	m_defined

int	m_bottomCells

Vector< MGLevelOp< T > * >	m_op

Vector< T *>	m_residual

Vector< T *>	m_correction

std::vector< bool >	m_ownOp

Private Member Functions
	MultiGrid (const MultiGrid< T > &a_opin)

void	operator= (const MultiGrid< T > &a_opin)

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.

Constructor & Destructor Documentation

◆ MultiGrid() [1/2]

template<class T >

MultiGrid< T >::MultiGrid ( )

◆ ~MultiGrid()

template<class T >

MultiGrid< T >::~MultiGrid ( )

virtual

References MultiGrid< T >::clear().

◆ MultiGrid() [2/2]

template<class T>

MultiGrid< T >::MultiGrid ( const MultiGrid< T > & a_opin )

inlineprivate

References MayDay::Error().

Member Function Documentation

◆ define()

template<class T >

void MultiGrid< T >::define	(	MGLevelOpFactory< T > &	a_factory,
		LinearSolver< T > *	a_bottomSolver,
		const ProblemDomain &	a_domain,
		int	a_maxDepth = `-1`,
		MGLevelOp< T > *	a_finestLevelOp = `NULL`
	)

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.

Reimplemented in FASMultiGrid< T >.

References Vector< T >::back(), CH_SPACEDIM, CH_TIME, MultiGrid< T >::clear(), ProblemDomain::domainBox(), 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_ownOp, MultiGrid< T >::m_residual, MultiGrid< T >::m_topLevelDomain, MGLevelOpFactory< T >::MGnewOp(), Box::numPts(), Vector< T >::push_back(), and Vector< T >::resize().

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

◆ solve()

template<class T >

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

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.

Reimplemented in FASMultiGrid< T >.

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

◆ oneCycle()

template<class T >

void MultiGrid< T >::oneCycle	(	T &	a_e,
		const T &	a_res
	)

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

Reimplemented in FASMultiGrid< T >.

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

◆ init()

template<class T >

void MultiGrid< T >::init	(	const T &	a_correction,
		const T &	a_residual
	)

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

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

◆ cycle()

template<class T >

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

References CH_TIME, 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().

◆ clear()

template<class T >

void MultiGrid< T >::clear ( )

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

Referenced by MultiGrid< T >::define(), and MultiGrid< T >::~MultiGrid().

◆ setBottomSolver()

template<class T >

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

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

◆ getAllOperators()

template<class T >

Vector< MGLevelOp< T > *> MultiGrid< T >::getAllOperators ( )

for changing coefficients — not for the faint of heart.

References MGLevelOpObserver< T >::m_op.

◆ operator=()

template<class T>

void MultiGrid< T >::operator= ( const MultiGrid< T > & a_opin )

inlineprivate

References MayDay::Error().

Member Data Documentation

◆ m_depth

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 FASMultiGrid< T >::cycle(), MultiGrid< T >::cycle(), MultiGrid< T >::define(), MultiGrid< T >::init(), FASMultiGrid< T >::oneCycle(), and MultiGrid< T >::setBottomSolver().