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

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

Public Types
using	time_type = typename FunctionTime< typename numbers::NumberTraits< RangeNumberType >::real_type >::time_type

Public Member Functions
	ZeroFunction (const unsigned int n_components=1)

virtual RangeNumberType	value (const Point< dim > &p, const unsigned int component=0) const override

virtual void	vector_value (const Point< dim > &p, Vector< RangeNumberType > &return_value) const override

virtual void	value_list (const std::vector< Point< dim > > &points, std::vector< RangeNumberType > &return_values, const unsigned int component=0) const override

virtual void	vector_value_list (const std::vector< Point< dim > > &points, std::vector< Vector< RangeNumberType > > &return_values) const override

virtual Tensor< 1, dim, RangeNumberType >	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, RangeNumberType > > &gradients) const override

virtual void	gradient_list (const std::vector< Point< dim > > &points, std::vector< Tensor< 1, dim, RangeNumberType > > &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, RangeNumberType > > > &gradients) const override

virtual SymmetricTensor< 2, dim, RangeNumberType >	hessian (const Point< dim > &point, const unsigned int component=0) const override

virtual RangeNumberType	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< RangeNumberType > > &values) const

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

virtual void	vector_laplacian (const Point< dim > &p, Vector< RangeNumberType > &values) const

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

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

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

virtual void	hessian_list (const std::vector< Point< dim > > &points, std::vector< SymmetricTensor< 2, dim, RangeNumberType > > &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, RangeNumberType > > > &values) const

Number	get_time () const

virtual void	set_time (const Number new_time)

virtual void	advance_time (const Number delta_t)

Public Attributes
const unsigned int	n_components

Static Public Attributes
static constexpr unsigned int	dimension = dim

Protected Attributes
std::vector< RangeNumberType >	function_value_vector

Private Attributes
Number	time

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)

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

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<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 510 of file function.h.

Member Typedef Documentation

◆ time_type

template<int dim, typename RangeNumberType = double>

using Function< dim, RangeNumberType >::time_type = typename FunctionTime< typename numbers::NumberTraits<RangeNumberType>::real_type>::time_type

inherited

The scalar-valued real type used for representing time.

Definition at line 169 of file function.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()

template<int dim, typename RangeNumberType = double>

virtual RangeNumberType Functions::ConstantFunction< dim, RangeNumberType >::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, RangeNumberType >.

◆ vector_value()

template<int dim, typename RangeNumberType = double>

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

overridevirtualinherited

Return all components of a vector-valued function at a given point.

values shall have the right size beforehand, i.e. n_components.

The default implementation will call value() for each component.

Reimplemented from Function< dim, RangeNumberType >.

Reimplemented in ComponentSelectFunction< dim, RangeNumberType >.

◆ value_list()

template<int dim, typename RangeNumberType = double>

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

overridevirtualinherited

Set values to the point values of the specified component 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.

By default, this function repeatedly calls value() for each point separately, to fill the output array.

Reimplemented from Function< dim, RangeNumberType >.

◆ vector_value_list()

template<int dim, typename RangeNumberType = double>

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

overridevirtualinherited

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, and that all elements be vectors with the same number of components as this function has.

By default, this function repeatedly calls vector_value() for each point separately, to fill the output array.

Reimplemented from Function< dim, RangeNumberType >.

Reimplemented in ComponentSelectFunction< dim, RangeNumberType >.

◆ gradient()

template<int dim, typename RangeNumberType = double>

virtual Tensor< 1, dim, RangeNumberType > Functions::ConstantFunction< dim, RangeNumberType >::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, RangeNumberType >.

◆ vector_gradient()

template<int dim, typename RangeNumberType = double>

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

overridevirtualinherited

Return the gradient of all components of the function at the given point.

Reimplemented from Function< dim, RangeNumberType >.

◆ gradient_list()

template<int dim, typename RangeNumberType = double>

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

overridevirtualinherited

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

Reimplemented from Function< dim, RangeNumberType >.

◆ vector_gradient_list()

template<int dim, typename RangeNumberType = double>

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

overridevirtualinherited

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

The outer loop over gradients is over the points in the list, the inner loop over the different components of the function.

Reimplemented from Function< dim, RangeNumberType >.

◆ hessian()

template<int dim, typename RangeNumberType = double>

virtual SymmetricTensor< 2, dim, RangeNumberType > Functions::ConstantFunction< dim, RangeNumberType >::hessian	(	const Point< dim > &	p,
		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, RangeNumberType >.

◆ laplacian()

template<int dim, typename RangeNumberType = double>

virtual RangeNumberType Functions::ConstantFunction< dim, RangeNumberType >::laplacian	(	const Point< dim > &	p,
		const unsigned int	component = `0`
	)		const

overridevirtualinherited

Compute the Laplacian of a given component at point p.

Reimplemented from Function< dim, RangeNumberType >.

◆ memory_consumption()

template<int dim, typename RangeNumberType = double>

virtual std::size_t Functions::ConstantFunction< dim, RangeNumberType >::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, RangeNumberType >.

Reimplemented in ComponentSelectFunction< dim, RangeNumberType >.

◆ vector_values()

template<int dim, typename RangeNumberType = double>

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

template<int dim, typename RangeNumberType = double>

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

template<int dim, typename RangeNumberType = double>

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

virtualinherited

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

Reimplemented in Functions::FEFieldFunction< dim, VectorType, spacedim >.

◆ laplacian_list()

template<int dim, typename RangeNumberType = double>

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

virtualinherited

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

Reimplemented in Functions::FEFieldFunction< dim, VectorType, spacedim >.

◆ vector_laplacian_list()

template<int dim, typename RangeNumberType = double>

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

virtualinherited

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

Reimplemented in Functions::FEFieldFunction< dim, VectorType, spacedim >.

◆ vector_hessian()

template<int dim, typename RangeNumberType = double>

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

virtualinherited

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

◆ hessian_list()

template<int dim, typename RangeNumberType = double>

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

virtualinherited

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

◆ vector_hessian_list()

template<int dim, typename RangeNumberType = double>

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

virtualinherited

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

◆ 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.

Member Data Documentation

◆ function_value_vector

template<int dim, typename RangeNumberType = double>

std::vector<RangeNumberType> Functions::ConstantFunction< dim, RangeNumberType >::function_value_vector

protectedinherited

Store the constant function value vector.

Definition at line 493 of file function.h.

◆ dimension

template<int dim, typename RangeNumberType = double>

constexpr unsigned int Function< dim, RangeNumberType >::dimension = dim

staticconstexprinherited

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

Definition at line 159 of file function.h.

◆ n_components

template<int dim, typename RangeNumberType = double>

const unsigned int Function< dim, RangeNumberType >::n_components

inherited

Number of vector components.

Definition at line 164 of file function.h.

◆ time

template<typename Number = double>

Number FunctionTime< Number >::time

privateinherited

Store the present time.

Definition at line 113 of file function_time.h.

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

include/deal.II/base/function.h

Public Types

Public Member Functions

Public Attributes

Static Public Attributes

Protected Attributes

Private Attributes

Subscriptor functionality

Detailed Description

Member Typedef Documentation

◆ time_type

Constructor & Destructor Documentation

◆ ZeroFunction()

Member Function Documentation

◆ value()

◆ vector_value()

◆ value_list()

◆ vector_value_list()

◆ gradient()

◆ vector_gradient()

◆ gradient_list()

◆ vector_gradient_list()

◆ hessian()

◆ laplacian()

◆ memory_consumption()

◆ vector_values()

◆ vector_gradients()

◆ vector_laplacian()

◆ laplacian_list()

◆ vector_laplacian_list()

◆ vector_hessian()

◆ hessian_list()

◆ vector_hessian_list()

◆ get_time()

◆ set_time()

◆ advance_time()

Member Data Documentation

◆ function_value_vector

◆ dimension

◆ n_components

◆ time