Reference documentation for deal.II version 9.6.0
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Functions::ZeroFunction< dim, RangeNumberType > Class Template Reference

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

Inheritance diagram for Functions::ZeroFunction< dim, RangeNumberType >:

Public Types

using time_type
 

Public Member Functions

 ZeroFunction (const unsigned int n_components=1)
 
virtual double value (const Point< dim > &p, const unsigned int component=0) const override
 
virtual void vector_value (const Point< dim > &p, Vector< double > &return_value) const override
 
virtual void value_list (const std::vector< Point< dim > > &points, std::vector< double > &return_values, const unsigned int component=0) const override
 
virtual void vector_value_list (const std::vector< Point< dim > > &points, std::vector< Vector< double > > &return_values) const override
 
virtual Tensor< 1, dim, double > gradient (const Point< dim > &p, const unsigned int component=0) const override
 
virtual void vector_gradient (const Point< dim > &p, std::vector< Tensor< 1, dim, double > > &gradients) const override
 
virtual void gradient_list (const std::vector< Point< dim > > &points, std::vector< Tensor< 1, dim, double > > &gradients, const unsigned int component=0) const override
 
virtual void vector_gradient_list (const std::vector< Point< dim > > &points, std::vector< std::vector< Tensor< 1, dim, double > > > &gradients) const override
 
virtual SymmetricTensor< 2, dim, double > hessian (const Point< dim > &point, const unsigned int component=0) const override
 
virtual double laplacian (const Point< dim > &point, const unsigned int component=0) const override
 
virtual std::size_t memory_consumption () const override
 
virtual void vector_values (const std::vector< Point< dim > > &points, std::vector< std::vector< double > > &values) const
 
virtual void vector_gradients (const std::vector< Point< dim > > &points, std::vector< std::vector< Tensor< 1, dim, double > > > &gradients) const
 
virtual void vector_laplacian (const Point< dim > &p, Vector< double > &values) const
 
virtual void laplacian_list (const std::vector< Point< dim > > &points, std::vector< double > &values, const unsigned int component=0) const
 
virtual void vector_laplacian_list (const std::vector< Point< dim > > &points, std::vector< Vector< double > > &values) const
 
virtual void vector_hessian (const Point< dim > &p, std::vector< SymmetricTensor< 2, dim, double > > &values) const
 
virtual void hessian_list (const std::vector< Point< dim > > &points, std::vector< SymmetricTensor< 2, dim, double > > &values, const unsigned int component=0) const
 
virtual void vector_hessian_list (const std::vector< Point< dim > > &points, std::vector< std::vector< SymmetricTensor< 2, dim, double > > > &values) const
 
numbers::NumberTraits< double >::real_type get_time () const
 
virtual void set_time (const numbers::NumberTraits< double >::real_type new_time)
 
virtual void advance_time (const numbers::NumberTraits< double >::real_type delta_t)
 
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 ::ExceptionBaseExcInUse (int arg1, std::string arg2, std::string arg3)
 
static ::ExceptionBaseExcNoSubscriber (std::string arg1, std::string arg2)
 

Public Attributes

const unsigned int n_components
 

Static Public Attributes

static constexpr unsigned int dimension
 

Protected Attributes

std::vector< double > function_value_vector
 

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

numbers::NumberTraits< double >::real_type time
 
std::atomic< unsigned intcounter
 
std::map< std::string, unsigned intcounter_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 dim, typename RangeNumberType = double>
class Functions::ZeroFunction< dim, RangeNumberType >

Provide a function which always returns zero. Obviously, also the derivatives of this function are zero. Also, it returns zero on all components in case the function is not a scalar one, which can be obtained by passing the constructor the appropriate number of components.

This function is of use when you want to implement homogeneous boundary conditions, or zero initial conditions.

Definition at line 509 of file function.h.

Member Typedef Documentation

◆ time_type

using Function< dim, double >::time_type
inherited

The scalar-valued real type used for representing time.

Definition at line 168 of file function.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

◆ ZeroFunction()

template<int dim, typename RangeNumberType = double>
Functions::ZeroFunction< dim, RangeNumberType >::ZeroFunction ( const unsigned int n_components = 1)
explicit

Constructor. The number of components is preset to one.

Member Function Documentation

◆ value()

virtual double Functions::ConstantFunction< dim, double >::value ( const Point< dim > & p,
const unsigned int component = 0 ) const
overridevirtualinherited

Return the value of the function at the given point. Unless there is only one component (i.e. the function is scalar), you should state the component you want to have evaluated; it defaults to zero, i.e. the first component.

Reimplemented from Function< dim, double >.

◆ vector_value()

virtual void Functions::ConstantFunction< dim, double >::vector_value ( const Point< dim > & p,
Vector< double > & values ) const
overridevirtualinherited

Reimplemented from Function< dim, double >.

◆ value_list()

virtual void Functions::ConstantFunction< dim, double >::value_list ( const std::vector< Point< dim > > & points,
std::vector< double > & values,
const unsigned int component = 0 ) const
overridevirtualinherited

Reimplemented from Function< dim, double >.

◆ vector_value_list()

virtual void Functions::ConstantFunction< dim, double >::vector_value_list ( const std::vector< Point< dim > > & points,
std::vector< Vector< double > > & values ) const
overridevirtualinherited

Reimplemented from Function< dim, double >.

◆ gradient()

virtual Tensor< 1, dim, double > Functions::ConstantFunction< dim, double >::gradient ( const Point< dim > & p,
const unsigned int component = 0 ) const
overridevirtualinherited

Return the gradient of the specified component of the function at the given point.

Reimplemented from Function< dim, double >.

◆ vector_gradient()

virtual void Functions::ConstantFunction< dim, double >::vector_gradient ( const Point< dim > & p,
std::vector< Tensor< 1, dim, double > > & gradients ) const
overridevirtualinherited

Reimplemented from Function< dim, double >.

◆ gradient_list()

virtual void Functions::ConstantFunction< dim, double >::gradient_list ( const std::vector< Point< dim > > & points,
std::vector< Tensor< 1, dim, double > > & gradients,
const unsigned int component = 0 ) const
overridevirtualinherited

Reimplemented from Function< dim, double >.

◆ vector_gradient_list()

virtual void Functions::ConstantFunction< dim, double >::vector_gradient_list ( const std::vector< Point< dim > > & points,
std::vector< std::vector< Tensor< 1, dim, double > > > & gradients ) const
overridevirtualinherited

Reimplemented from Function< dim, double >.

◆ hessian()

virtual SymmetricTensor< 2, dim, double > Functions::ConstantFunction< dim, double >::hessian ( const Point< dim > & point,
const unsigned int component = 0 ) const
overridevirtualinherited

Compute the Hessian of a given component at point p, that is the gradient of the gradient of the function.

Reimplemented from Function< dim, double >.

◆ laplacian()

virtual double Functions::ConstantFunction< dim, double >::laplacian ( const Point< dim > & point,
const unsigned int component = 0 ) const
overridevirtualinherited

Compute the Laplacian of a given component at point p.

Reimplemented from Function< dim, double >.

◆ memory_consumption()

virtual std::size_t Functions::ConstantFunction< dim, double >::memory_consumption ( ) const
overridevirtualinherited

Return an estimate for the memory consumption, in bytes, of this object.

This function is virtual and can be overloaded by derived classes.

Reimplemented from Function< dim, double >.

Reimplemented in ComponentSelectFunction< dim, RangeNumberType >.

◆ vector_values()

virtual void Function< dim, double >::vector_values ( const std::vector< Point< dim > > & points,
std::vector< std::vector< double > > & values ) const
virtualinherited

For each component of the function, fill a vector of values, one for each point.

The default implementation of this function in Function calls value_list() for each component. In order to improve performance, this can be reimplemented in derived classes to speed up performance.

◆ vector_gradients()

virtual void Function< dim, double >::vector_gradients ( const std::vector< Point< dim > > & points,
std::vector< std::vector< Tensor< 1, dim, double > > > & gradients ) const
virtualinherited

For each component of the function, fill a vector of gradient values, one for each point.

The default implementation of this function in Function calls value_list() for each component. In order to improve performance, this can be reimplemented in derived classes to speed up performance.

◆ vector_laplacian()

virtual void Function< dim, double >::vector_laplacian ( const Point< dim > & p,
Vector< double > & values ) const
virtualinherited

Compute the Laplacian of all components at point p and store them in values.

◆ laplacian_list()

virtual void Function< dim, double >::laplacian_list ( const std::vector< Point< dim > > & points,
std::vector< double > & values,
const unsigned int component = 0 ) const
virtualinherited

Compute the Laplacian of one component at a set of points.

◆ vector_laplacian_list()

virtual void Function< dim, double >::vector_laplacian_list ( const std::vector< Point< dim > > & points,
std::vector< Vector< double > > & values ) const
virtualinherited

Compute the Laplacians of all components at a set of points.

◆ vector_hessian()

virtual void Function< dim, double >::vector_hessian ( const Point< dim > & p,
std::vector< SymmetricTensor< 2, dim, double > > & values ) const
virtualinherited

Compute the Hessian of all components at point p and store them in values.

◆ hessian_list()

virtual void Function< dim, double >::hessian_list ( const std::vector< Point< dim > > & points,
std::vector< SymmetricTensor< 2, dim, double > > & values,
const unsigned int component = 0 ) const
virtualinherited

Compute the Hessian of one component at a set of points.

◆ vector_hessian_list()

virtual void Function< dim, double >::vector_hessian_list ( const std::vector< Point< dim > > & points,
std::vector< std::vector< SymmetricTensor< 2, dim, double > > > & values ) const
virtualinherited

Compute the Hessians of all components at a set of points.

◆ get_time()

numbers::NumberTraits< double >::real_type FunctionTime< numbers::NumberTraits< double >::real_type >::get_time ( ) const
inherited

Return the value of the time variable.

◆ set_time()

virtual void FunctionTime< numbers::NumberTraits< double >::real_type >::set_time ( const numbers::NumberTraits< double >::real_type new_time)
virtualinherited

Set the time to new_time, overwriting the old value.

◆ advance_time()

virtual void FunctionTime< numbers::NumberTraits< double >::real_type >::advance_time ( const numbers::NumberTraits< double >::real_type delta_t)
virtualinherited

Advance the time by the given time step delta_t.

◆ 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

◆ function_value_vector

std::vector<double> Functions::ConstantFunction< dim, double >::function_value_vector
protectedinherited

Store the constant function value vector.

Definition at line 492 of file function.h.

◆ dimension

unsigned int Function< dim, double >::dimension
staticconstexprinherited

Export the value of the template parameter as a static member constant. Sometimes useful for some expression template programming.

Definition at line 158 of file function.h.

◆ n_components

const unsigned int Function< dim, double >::n_components
inherited

Number of vector components.

Definition at line 163 of file function.h.

◆ time

numbers::NumberTraits< double >::real_type FunctionTime< numbers::NumberTraits< double >::real_type >::time
privateinherited

Store the present time.

Definition at line 112 of file function_time.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.


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