MatrixFreeOperators::MGInterfaceOperator< OperatorType > Class Template Reference

#include <deal.II/matrix_free/operators.h>

Inheritance diagram for MatrixFreeOperators::MGInterfaceOperator< OperatorType >:

Public Types
using	value_type = typename OperatorType::value_type
using	size_type = typename OperatorType::size_type

Public Member Functions
	MGInterfaceOperator ()
void	clear ()
void	initialize (const OperatorType &operator_in)
template<typename VectorType >
void	vmult (VectorType &dst, const VectorType &src) const
template<typename VectorType >
void	Tvmult (VectorType &dst, const VectorType &src) const
template<typename VectorType >
void	initialize_dof_vector (VectorType &vec) const
template<class Archive >
void	serialize (Archive &ar, const unsigned int version)
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

Static Public Member Functions
static ::ExceptionBase &	ExcInUse (int arg1, std::string arg2, std::string arg3)
static ::ExceptionBase &	ExcNoSubscriber (std::string arg1, std::string arg2)

Private Types
using	map_value_type = decltype(counter_map)::value_type
using	map_iterator = decltype(counter_map)::iterator

Private Member Functions
void	check_no_subscribers () const noexcept

Private Attributes
SmartPointer< const OperatorType >	mf_base_operator
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 Private Attributes
static std::mutex	mutex

Detailed Description

template<typename OperatorType>
class MatrixFreeOperators::MGInterfaceOperator< OperatorType >

Auxiliary class to provide interface vmult/Tvmult methods required in adaptive geometric multgrids. OperatorType class should be derived from MatrixFreeOperators::Base class.

The adaptive multigrid realization in deal.II implements an approach called local smoothing. This means that the smoothing on the finest level only covers the local part of the mesh defined by the fixed (finest) grid level and ignores parts of the computational domain where the terminal cells are coarser than this level. As the method progresses to coarser levels, more and more of the global mesh will be covered. At some coarser level, the whole mesh will be covered. Since all level matrices in the multigrid method cover a single level in the mesh, no hanging nodes appear on the level matrices. At the interface between multigrid levels, homogeneous Dirichlet boundary conditions are set while smoothing. When the residual is transferred to the next coarser level, however, the coupling over the multigrid interface needs to be taken into account. This is done by the so-called interface (or edge) matrices that compute the part of the residual that is missed by the level matrix with homogeneous Dirichlet conditions. We refer to the Multigrid paper by Janssen and Kanschat for more details.

For the implementation of those interface matrices, most infrastructure is already in place and provided by MatrixFreeOperators::Base through the two multiplication routines vmult_interface_down() and vmult_interface_up(). The only thing MGInterfaceOperator does is wrapping those operations and make them accessible via vmult() and Tvmult interface as expected by the multigrid routines (that were originally written for matrices, hence expecting those names). Note that the vmult_interface_down is used during the restriction phase of the multigrid V-cycle, whereas vmult_interface_up is used during the prolongation phase.

Definition at line 537 of file operators.h.

Member Typedef Documentation

value_type

template<typename OperatorType >

using MatrixFreeOperators::MGInterfaceOperator< OperatorType >::value_type = typename OperatorType::value_type

Number alias.

Definition at line 543 of file operators.h.

size_type

template<typename OperatorType >

using MatrixFreeOperators::MGInterfaceOperator< OperatorType >::size_type = typename OperatorType::size_type

Size type.

Definition at line 548 of file operators.h.

map_value_type

using Subscriptor::map_value_type = decltype(counter_map)::value_type

privateinherited

The data type used in counter_map.

Definition at line 229 of file subscriptor.h.

map_iterator

using Subscriptor::map_iterator = decltype(counter_map)::iterator

privateinherited

The iterator type used in counter_map.

Definition at line 234 of file subscriptor.h.

Constructor & Destructor Documentation

MGInterfaceOperator()

template<typename OperatorType >

MatrixFreeOperators::MGInterfaceOperator< OperatorType >::MGInterfaceOperator

(

)

Default constructor.

Definition at line 1807 of file operators.h.

Member Function Documentation

clear()

template<typename OperatorType >

void MatrixFreeOperators::MGInterfaceOperator< OperatorType >::clear

(

)

Clear the pointer to the OperatorType object.

Definition at line 1816 of file operators.h.

initialize()

template<typename OperatorType >

void MatrixFreeOperators::MGInterfaceOperator< OperatorType >::initialize

(

const OperatorType &

operator_in

)

Initialize this class with an operator operator_in.

Definition at line 1825 of file operators.h.

vmult()

template<typename OperatorType >

template<typename VectorType >

void MatrixFreeOperators::MGInterfaceOperator< OperatorType >::vmult	(	VectorType &	dst,
		const VectorType &	src ) const

vmult operator, see class description for more info.

Definition at line 1835 of file operators.h.

Tvmult()

template<typename OperatorType >

template<typename VectorType >

void MatrixFreeOperators::MGInterfaceOperator< OperatorType >::Tvmult	(	VectorType &	dst,
		const VectorType &	src ) const

Tvmult operator, see class description for more info.

Definition at line 1855 of file operators.h.

initialize_dof_vector()

template<typename OperatorType >

template<typename VectorType >

void MatrixFreeOperators::MGInterfaceOperator< OperatorType >::initialize_dof_vector

(

VectorType &

vec

)

const

A wrapper for initialize_dof_vector() of OperatorType object.

Definition at line 1875 of file operators.h.

subscribe()

void Subscriptor::subscribe ( std::atomic< bool > *const validity, const std::string & identifier = "" ) const

inherited

Subscribes a user of the object by storing the pointer validity. The subscriber may be identified by text supplied as identifier.

Definition at line 135 of file subscriptor.cc.

unsubscribe()

void Subscriptor::unsubscribe ( std::atomic< bool > *const validity, const std::string & identifier = "" ) const

inherited

Unsubscribes a user from the object.

Note

The identifier and the validity pointer must be the same as the one supplied to subscribe().

Definition at line 155 of file subscriptor.cc.

n_subscriptions()

unsigned int Subscriptor::n_subscriptions ( ) const

inlineinherited

Return the present number of subscriptions to this object. This allows to use this class for reference counted lifetime determination where the last one to unsubscribe also deletes the object.

Definition at line 300 of file subscriptor.h.

list_subscribers() [1/2]

template<typename StreamType >

void Subscriptor::list_subscribers ( StreamType & stream ) const

inlineinherited

List the subscribers to the input stream.

Definition at line 317 of file subscriptor.h.

list_subscribers() [2/2]

void Subscriptor::list_subscribers ( ) const

inherited

List the subscribers to deallog.

Definition at line 203 of file subscriptor.cc.

serialize()

template<class Archive >

void Subscriptor::serialize ( Archive & ar, const unsigned int version )

inlineinherited

Read or write the data of this object to or from a stream for the purpose of serialization using the BOOST serialization library.

This function does not actually serialize any of the member variables of this class. The reason is that what this class stores is only who subscribes to this object, but who does so at the time of storing the contents of this object does not necessarily have anything to do with who subscribes to the object when it is restored. Consequently, we do not want to overwrite the subscribers at the time of restoring, and then there is no reason to write the subscribers out in the first place.

Definition at line 309 of file subscriptor.h.

check_no_subscribers()

void Subscriptor::check_no_subscribers ( ) const

privatenoexceptinherited

Check that there are no objects subscribing to this object. If this check passes then it is safe to destroy the current object. It this check fails then this function will either abort or print an error message to deallog (by using the AssertNothrow mechanism), but will not throw an exception.

Note

Since this function is just a consistency check it does nothing in release mode.

If this function is called when there is an uncaught exception then, rather than aborting, this function prints an error message to the standard error stream and returns.

Definition at line 52 of file subscriptor.cc.

Member Data Documentation

mf_base_operator

template<typename OperatorType >

SmartPointer<const OperatorType> MatrixFreeOperators::MGInterfaceOperator< OperatorType >::mf_base_operator

private

Const pointer to the operator class.

Definition at line 593 of file operators.h.

counter

std::atomic<unsigned int> Subscriptor::counter

mutableprivateinherited

Store the number of objects which subscribed to this object. Initially, this number is zero, and upon destruction it shall be zero again (i.e. all objects which subscribed should have unsubscribed again).

The creator (and owner) of an object is counted in the map below if HE manages to supply identification.

We use the mutable keyword in order to allow subscription to constant objects also.

This counter may be read from and written to concurrently in multithreaded code: hence we use the std::atomic class template.

Definition at line 218 of file subscriptor.h.

counter_map

std::map<std::string, unsigned int> Subscriptor::counter_map

mutableprivateinherited

In this map, we count subscriptions for each different identification string supplied to subscribe().

Definition at line 224 of file subscriptor.h.

validity_pointers

std::vector<std::atomic<bool> *> Subscriptor::validity_pointers

mutableprivateinherited

In this vector, we store pointers to the validity bool in the SmartPointer objects that subscribe to this class.

Definition at line 240 of file subscriptor.h.

object_info

const std::type_info* Subscriptor::object_info

mutableprivateinherited

Pointer to the typeinfo object of this object, from which we can later deduce the class name. Since this information on the derived class is neither available in the destructor, nor in the constructor, we obtain it in between and store it here.

Definition at line 248 of file subscriptor.h.

mutex

std::mutex Subscriptor::mutex

staticprivateinherited

A mutex used to ensure data consistency when accessing the mutable members of this class. This lock is used in the subscribe() and unsubscribe() functions, as well as in list_subscribers().

Definition at line 271 of file subscriptor.h.

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

• include/deal.II/matrix_free/operators.h