MGLevelObject< Object > Class Template Reference

#include <deal.II/base/mg_level_object.h>

Inheritance diagram for MGLevelObject< Object >:

Public Member Functions
template<class... Args>
	MGLevelObject (const unsigned int minlevel, const unsigned int maxlevel, Args &&... args)
	MGLevelObject (const unsigned int minlevel=0, const unsigned int maxlevel=0)
Object &	operator[] (const unsigned int level)
const Object &	operator[] (const unsigned int level) const
template<class... Args>
void	resize (const unsigned int new_minlevel, const unsigned int new_maxlevel, Args &&... args)
MGLevelObject< Object > &	operator= (const double d)
void	clear_elements ()
unsigned int	min_level () const
unsigned int	max_level () const
template<typename ActionFunctionObjectType >
void	apply (ActionFunctionObjectType action)
std::size_t	memory_consumption () const

Private Attributes
unsigned int	minlevel
std::vector< std::shared_ptr< Object > >	objects

Subscriptor functionality
Classes derived from Subscriptor provide a facility to subscribe to this object. This is mostly used by the SmartPointer class.
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
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
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<class Object>
class MGLevelObject< Object >

This class represents an array with one object for each used level of a multilevel hierarchy, for example for use in the multigrid algorithms. In contrast to just a generic std::vector, this class allows to store objects only between some minimal and maximal index (=level), as one often wants to run a multilevel algorithm only on a subset of the levels of a mesh (e.g., because the second or third coarsest level is already small enough that it is cheaper to run a direct solver there, rather than recurse to even coarser levels). Despite storing objects only for these "interesting" levels, the class allows indexing simply by level. Internally, this is of course done by simply shifting the given index by the minimum level we have stored.

In a typical use case for this class, the objects stored on each level are either matrices or vectors.

Definition at line 49 of file mg_level_object.h.

Constructor & Destructor Documentation

MGLevelObject() [1/2]

template<class Object >

template<class... Args>

MGLevelObject< Object >::MGLevelObject	(	const unsigned int	minlevel,
		const unsigned int	maxlevel,
		Args &&...	args
	)

Constructor. Create a multilevel object with given minimal and maximal level, and allocate storage for objects on maxlevel-minlevel+1 levels.

Note

Unlike in many other places of the library, the two arguments here do not denote the first level and last-plus-one level, but indeed an inclusive range of levels for which to allocate storage for level objects. Consequently, the defaults for the two arguments will create an array with one level object, rather than an empty array.

Parameters

[in]	minlevel	The lowest level for which to provision memory for level objects.
[in]	maxlevel	The highest level for which to provision memory for level objects.
[in]	args	Optional arguments passed to the constructor of the underlying object.

Precondition

minlevel <= maxlevel

Definition at line 187 of file mg_level_object.h.

MGLevelObject() [2/2]

template<class Object >

MGLevelObject< Object >::MGLevelObject	(	const unsigned int	minlevel = 0,
		const unsigned int	maxlevel = 0
	)

Constructor. Same as above but without arguments to be forwarded to the constructor of the underlying object.

Definition at line 197 of file mg_level_object.h.

Member Function Documentation

operator[]() [1/2]

template<class Object >

Object & MGLevelObject< Object >::operator[]

(

const unsigned int

level

)

Access object on level level.

Definition at line 206 of file mg_level_object.h.

operator[]() [2/2]

template<class Object >

const Object & MGLevelObject< Object >::operator[]

(

const unsigned int

level

)

const

Access object on level level.

This function can be called on a const object, and consequently returns a const reference.

Definition at line 215 of file mg_level_object.h.

resize()

template<class Object >

template<class... Args>

void MGLevelObject< Object >::resize	(	const unsigned int	new_minlevel,
		const unsigned int	new_maxlevel,
		Args &&...	args
	)

Delete all previous contents of this object and reset its size according to the values of new_minlevel and new_maxlevel.

Parameters

[in]	new_minlevel	The lowest level for which to provision memory for level objects.
[in]	new_maxlevel	The highest level for which to provision memory for level objects.
[in]	args	Optional arguments passed to the constructor of the underlying object.

Precondition

minlevel <= maxlevel

Definition at line 226 of file mg_level_object.h.

operator=()

template<class Object >

MGLevelObject< Object > & MGLevelObject< Object >::operator=

(

const double

d

)

Call operator = (s) on all objects stored by this object. This clearly requires that the objects stored on each level allow for this operation. This is, in particular, true for vectors and matrices if d is zero, thereby zeroing out all vector or matrix entries.

Definition at line 245 of file mg_level_object.h.

clear_elements()

template<class Object >

void MGLevelObject< Object >::clear_elements

Call clear on all objects stored by this object. This function is only implemented for some Object classes, e.g., matrix types or the PreconditionBlockSOR and similar classes. Using this function will fail with a compiler error if the Object template type to this class does not provide a clear() member function.

Definition at line 256 of file mg_level_object.h.

min_level()

template<class Object >

unsigned int MGLevelObject< Object >::min_level

The coarsest level for which this class stores a level object.

Definition at line 266 of file mg_level_object.h.

max_level()

template<class Object >

unsigned int MGLevelObject< Object >::max_level

The highest level for which this class stores a level object.

Definition at line 274 of file mg_level_object.h.

apply()

template<class Object >

template<typename ActionFunctionObjectType >

void MGLevelObject< Object >::apply

(

ActionFunctionObjectType

action

)

Apply the action action to every object stored in here. The parameter action is expected to be a function object that accepts the syntax action(const unsigned int level, Object &object); This means this function can accept a lambda, a std::function, or a plain function pointer.

Definition at line 282 of file mg_level_object.h.

memory_consumption()

template<class Object >

std::size_t MGLevelObject< Object >::memory_consumption

Memory used by this object.

Definition at line 293 of file mg_level_object.h.

Member Data Documentation

minlevel

template<class Object >

unsigned int MGLevelObject< Object >::minlevel

private

Level of first component.

Definition at line 173 of file mg_level_object.h.

objects

template<class Object >

std::vector<std::shared_ptr<Object> > MGLevelObject< Object >::objects

private

Array of the objects to be held.

Definition at line 178 of file mg_level_object.h.

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

• include/deal.II/base/mg_level_object.h