MGSmootherIdentity< VectorType > Class Template Reference

#include <deal.II/multigrid/mg_smoother.h>

Inheritance diagram for MGSmootherIdentity< VectorType >:

Public Member Functions
virtual void	smooth (const unsigned int level, VectorType &u, const VectorType &rhs) const
virtual void	clear ()
virtual void	apply (const unsigned int level, VectorType &u, const VectorType &rhs) const

Subscriptor functionality
Classes derived from Subscriptor provide a facility to subscribe to this object. This is mostly used by the SmartPointer class.
void	subscribe (std::atomic< bool > *const validity, const std::string &identifier="") const
void	unsubscribe (std::atomic< bool > *const validity, const std::string &identifier="") const
unsigned int	n_subscriptions () const
template<typename StreamType >
void	list_subscribers (StreamType &stream) const
void	list_subscribers () const
template<class Archive >
void	serialize (Archive &ar, const unsigned int version)
using	map_value_type = decltype(counter_map)::value_type
using	map_iterator = decltype(counter_map)::iterator
std::atomic< unsigned int >	counter
std::map< std::string, unsigned int >	counter_map
std::vector< std::atomic< bool > * >	validity_pointers
const std::type_info *	object_info
static std::mutex	mutex
static ::ExceptionBase &	ExcInUse (int arg1, std::string arg2, std::string arg3)
static ::ExceptionBase &	ExcNoSubscriber (std::string arg1, std::string arg2)
void	check_no_subscribers () const noexcept

Detailed Description

template<typename VectorType>
class MGSmootherIdentity< VectorType >

Smoother doing nothing. This class is not useful for many applications other than for testing some multigrid procedures. Also some applications might get convergence without smoothing and then this class brings you the cheapest possible multigrid.

Definition at line 138 of file mg_smoother.h.

Member Function Documentation

smooth()

template<typename VectorType >

virtual void MGSmootherIdentity< VectorType >::smooth ( const unsigned int  level, VectorType &  u, const VectorType &  rhs  ) const

virtual

Implementation of the interface for Multigrid. This function does nothing, which by comparison with the definition of this function means that the smoothing operator equals the null operator.

Implements MGSmootherBase< VectorType >.

clear()

template<typename VectorType >

virtual void MGSmootherIdentity< VectorType >::clear ( )

virtual

Release matrices.

Implements MGSmootherBase< VectorType >.

apply()

template<typename VectorType >

void MGSmootherBase< VectorType >::apply ( const unsigned int  level, VectorType &  u, const VectorType &  rhs  ) const

virtualinherited

As opposed to the smooth() function, this function applies the action of the smoothing, overwriting the previous content in the vector u. This function must be equivalent to the following code

u = 0;
smooth(level, u, rhs);

but can usually be implemented more efficiently than the former. If a particular smoother does not override the apply() method, the default implementation as described here is used.

In the multigrid preconditioner interfaces, the apply() method is used for the pre-smoothing operation because the previous content in the solution vector needs to be overwritten for a new incoming residual. On the other hand, all subsequent operations need to smooth the content already present in the vector u given the right hand side, which is done by smooth().

Reimplemented in MGSmootherRelaxation< MatrixType, RelaxationType, VectorType >, mg::SmootherRelaxation< RelaxationType, VectorType >, and MGSmootherPrecondition< MatrixType, PreconditionerType, VectorType >.

Definition at line 35 of file mg_base.cc.

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

• include/deal.II/multigrid/mg_smoother.h