TensorFunction< rank, dim, Number > Class Template Reference

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

Inheritance diagram for TensorFunction< rank, dim, Number >:

Public Types
using	value_type = Tensor< rank, dim, Number >
using	gradient_type = Tensor< rank+1, dim, Number >
using	time_type = typename FunctionTime< typename numbers::NumberTraits< Number >::real_type >::time_type

Public Member Functions
	TensorFunction (const time_type initial_time=time_type(0.0))
virtual	~TensorFunction () override=default
virtual value_type	value (const Point< dim > &p) const
virtual void	value_list (const std::vector< Point< dim > > &points, std::vector< value_type > &values) const
virtual gradient_type	gradient (const Point< dim > &p) const
virtual void	gradient_list (const std::vector< Point< dim > > &points, std::vector< gradient_type > &gradients) const
Number	get_time () const
virtual void	set_time (const Number new_time)
virtual void	advance_time (const Number delta_t)
template<class Archive >
void	serialize (Archive &ar, const unsigned int version)
EnableObserverPointer functionality
Classes derived from EnableObserverPointer provide a facility to subscribe to this object. This is mostly used by the ObserverPointer 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
Number	time
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<int rank, int dim, typename Number = double>
class TensorFunction< rank, dim, Number >

This class is a model for a tensor valued function. The interface of the class is mostly the same as that for the Function class, with the exception that it does not support vector-valued functions with several components, but that the return type is always tensor-valued. The returned values of the evaluation of objects of this type are always whole tensors, while for the Function class, one can ask for a specific component only, or use the vector_value function, which however does not return the value, but rather writes it into the address provided by its second argument. The reason for the different behavior of the classes is that in the case of tensor valued functions, the size of the argument is known to the compiler a priori, such that the correct amount of memory can be allocated on the stack for the return value; on the other hand, for the vector valued functions, the size is not known to the compiler, so memory has to be allocated on the heap, resulting in relatively expensive copy operations. One can therefore consider this class a specialization of the Function class for which the size is known. An additional benefit is that tensors of arbitrary rank can be returned, not only vectors, as for them the size can be determined similarly simply.

Definition at line 55 of file tensor_function.h.

Member Typedef Documentation

value_type

template<int rank, int dim, typename Number = double>

using TensorFunction< rank, dim, Number >::value_type = Tensor<rank, dim, Number>

Alias for the return types of the value function.

Definition at line 63 of file tensor_function.h.

gradient_type

template<int rank, int dim, typename Number = double>

using TensorFunction< rank, dim, Number >::gradient_type = Tensor<rank + 1, dim, Number>

Alias for the return types of the gradient functions.

Definition at line 68 of file tensor_function.h.

time_type

template<int rank, int dim, typename Number = double>

using TensorFunction< rank, dim, Number >::time_type = typename FunctionTime< typename numbers::NumberTraits<Number>::real_type>::time_type

The scalar-valued real type used for representing time.

Definition at line 73 of file tensor_function.h.

map_value_type

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

privateinherited

The data type used in counter_map.

Definition at line 238 of file enable_observer_pointer.h.

map_iterator

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

privateinherited

The iterator type used in counter_map.

Definition at line 243 of file enable_observer_pointer.h.

Constructor & Destructor Documentation

TensorFunction()

template<int rank, int dim, typename Number = double>

TensorFunction< rank, dim, Number >::TensorFunction

(

const time_type

initial_time = time_type(0.0)

)

Constructor. May take an initial value for the time variable, which defaults to zero.

~TensorFunction()

template<int rank, int dim, typename Number = double>

virtual TensorFunction< rank, dim, Number >::~TensorFunction ( )

overridevirtualdefault

Virtual destructor; absolutely necessary in this case, as classes are usually not used by their true type, but rather through pointers to this base class.

Member Function Documentation

value()

template<int rank, int dim, typename Number = double>

virtual value_type TensorFunction< rank, dim, Number >::value ( const Point< dim > &  p ) const

virtual

Return the value of the function at the given point.

Reimplemented in ConstantTensorFunction< rank, dim, Number >, ConstantTensorFunction< rank, dim, double >, and TensorFunctionParser< rank, dim, Number >.

value_list()

template<int rank, int dim, typename Number = double>

virtual void TensorFunction< rank, dim, Number >::value_list ( const std::vector< Point< dim > > &  points, std::vector< value_type > &  values  ) const

virtual

Set values to the point values of the function at the points. It is assumed that values already has the right size, i.e. the same size as the points array.

Reimplemented in TensorFunctionParser< rank, dim, Number >.

gradient()

template<int rank, int dim, typename Number = double>

virtual gradient_type TensorFunction< rank, dim, Number >::gradient ( const Point< dim > &  p ) const

virtual

Return the gradient of the function at the given point.

Reimplemented in ConstantTensorFunction< rank, dim, Number >, and ConstantTensorFunction< rank, dim, double >.

gradient_list()

template<int rank, int dim, typename Number = double>

virtual void TensorFunction< rank, dim, Number >::gradient_list ( const std::vector< Point< dim > > &  points, std::vector< gradient_type > &  gradients  ) const

virtual

Set gradients to the gradients of the function at the points. It is assumed that values already has the right size, i.e. the same size as the points array.

get_time()

template<typename Number = double>

Number FunctionTime< Number >::get_time ( ) const

inherited

Return the value of the time variable.

set_time()

template<typename Number = double>

virtual void FunctionTime< Number >::set_time ( const Number  new_time )

virtualinherited

Set the time to new_time, overwriting the old value.

advance_time()

template<typename Number = double>

virtual void FunctionTime< Number >::advance_time ( const Number  delta_t )

virtualinherited

Advance the time by the given time step delta_t.

subscribe()

void EnableObserverPointer::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 131 of file enable_observer_pointer.cc.

unsubscribe()

void EnableObserverPointer::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 151 of file enable_observer_pointer.cc.

n_subscriptions()

unsigned int EnableObserverPointer::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 322 of file enable_observer_pointer.h.

list_subscribers() [1/2]

template<typename StreamType >

void EnableObserverPointer::list_subscribers ( StreamType &  stream ) const

inlineinherited

List the subscribers to the input stream.

Definition at line 339 of file enable_observer_pointer.h.

list_subscribers() [2/2]

void EnableObserverPointer::list_subscribers ( ) const

inherited

List the subscribers to deallog.

Definition at line 199 of file enable_observer_pointer.cc.

serialize()

template<class Archive >

void EnableObserverPointer::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 331 of file enable_observer_pointer.h.

check_no_subscribers()

void EnableObserverPointer::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 53 of file enable_observer_pointer.cc.

Member Data Documentation

time

template<typename Number = double>

Number FunctionTime< Number >::time

privateinherited

Store the present time.

Definition at line 112 of file function_time.h.

counter

std::atomic<unsigned int> EnableObserverPointer::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 227 of file enable_observer_pointer.h.

counter_map

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

mutableprivateinherited

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

Definition at line 233 of file enable_observer_pointer.h.

validity_pointers

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

mutableprivateinherited

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

Definition at line 249 of file enable_observer_pointer.h.

object_info

const std::type_info* EnableObserverPointer::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 257 of file enable_observer_pointer.h.

mutex

std::mutex EnableObserverPointer::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 280 of file enable_observer_pointer.h.

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

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