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

Inheritance diagram for VectorFunctionFromScalarFunctionObject< dim, RangeNumberType >:

Public Member Functions
	VectorFunctionFromScalarFunctionObject (const std::function< RangeNumberType(const Point< dim > &)> &function_object, const unsigned int selected_component, const unsigned int n_components)

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

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

Public Member Functions inherited from Function< dim, double >
	Function (const unsigned int n_components=1, const time_type initial_time=0.0)

	Function (const Function &f)=default

virtual	~Function () override=0

Function &	operator= (const Function &f)

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

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

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

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

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

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

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

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

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

virtual double	laplacian (const Point< dim > &p, const unsigned int component=0) 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 SymmetricTensor< 2, dim, double >	hessian (const Point< dim > &p, const unsigned int component=0) 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

std::size_t	memory_consumption () const

Public Member Functions inherited from FunctionTime< numbers::NumberTraits< double >::real_type >
	FunctionTime (const numbers::NumberTraits< double >::real_type initial_time=numbers::NumberTraits< double >::real_type(0.0))

virtual	~FunctionTime ()=default

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)

Public Member Functions inherited from Subscriptor
	Subscriptor ()

	Subscriptor (const Subscriptor &)

	Subscriptor (Subscriptor &&) noexcept

virtual	~Subscriptor ()

Subscriptor &	operator= (const Subscriptor &)

Subscriptor &	operator= (Subscriptor &&) noexcept

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)

Private Attributes
const std::function< RangeNumberType(const Point< dim > &)>	function_object

const unsigned int	selected_component

Additional Inherited Members
Public Types inherited from Function< dim, double >
using	time_type = typename FunctionTime< typename numbers::NumberTraits< double >::real_type >::time_type

Public Types inherited from FunctionTime< numbers::NumberTraits< double >::real_type >
using	time_type = numbers::NumberTraits< double >::real_type

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

static ::ExceptionBase &	ExcNoSubscriber (std::string arg1, std::string arg2)

Public Attributes inherited from Function< dim, double >
const unsigned int	n_components

Static Public Attributes inherited from Function< dim, double >
static const unsigned int	dimension

Detailed Description

template<int dim, typename RangeNumberType = double>
class VectorFunctionFromScalarFunctionObject< dim, RangeNumberType >

This class is similar to the ScalarFunctionFromFunctionObject class in that it allows for the easy conversion of a function object to something that satisfies the interface of the Function base class. The difference is that here, the given function object is still a scalar function (i.e. it has a single value at each space point) but that the Function object generated is vector valued. The number of vector components is specified in the constructor, where one also selects a single one of these vector components that should be filled by the passed object. The result is a vector Function object that returns zero in each component except the single selected one where it returns the value returned by the given as the first argument to the constructor.

Note: In the above discussion, note the difference between the (scalar) "function object" (i.e., a C++ object x that can be called as in x(p)) and the capitalized (vector valued) "Function object" (i.e., an object of a class that is derived from the Function base class).

To be more concrete, let us consider the following example:

RangeNumberType
one(const Point<2> &p)
{
  return 1.0;
}
 
VectorFunctionFromScalarFunctionObject<2, RangeNumberType>
  component_mask(&one, 1, 3);

Here, component_mask then represents a Function object that for every point returns the vector \((0, 1, 0)^T\), i.e. a mask function that could, for example, be passed to VectorTools::integrate_difference(). This effect can also be achieved using the ComponentSelectFunction class but is obviously easily extended to functions that are non-constant in their one component.

Author: Wolfgang Bangerth, 2011

Definition at line 795 of file function.h.

Constructor & Destructor Documentation

◆ VectorFunctionFromScalarFunctionObject()

template<int dim, typename RangeNumberType = double>

VectorFunctionFromScalarFunctionObject< dim, RangeNumberType >::VectorFunctionFromScalarFunctionObject	(	const std::function< RangeNumberType(const Point< dim > &)> &	function_object,
		const unsigned int	selected_component,
		const unsigned int	n_components
	)

Given a function object that takes a Point and returns a RangeNumberType value, convert this into an object that matches the Function<dim> interface.

Parameters

function_object	The scalar function that will form one component of the resulting Function object.
n_components	The total number of vector components of the resulting Function object.
selected_component	The single component that should be filled by the first argument.

Member Function Documentation

◆ value()

template<int dim, typename RangeNumberType = double>

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

overridevirtual

Return the value of the function at the given point. Returns the value the function given to the constructor produces for this point.

Reimplemented from Function< dim, double >.

◆ vector_value()

template<int dim, typename RangeNumberType = double>

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

overridevirtual

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

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

Member Data Documentation

◆ function_object

template<int dim, typename RangeNumberType = double>

const std::function<RangeNumberType(const Point<dim> &)> VectorFunctionFromScalarFunctionObject< dim, RangeNumberType >::function_object

private

The function object which we call when this class's value() or value_list() functions are called.

Definition at line 837 of file function.h.

◆ selected_component

template<int dim, typename RangeNumberType = double>

const unsigned int VectorFunctionFromScalarFunctionObject< dim, RangeNumberType >::selected_component

private

The vector component whose value is to be filled by the given scalar function.

Definition at line 843 of file function.h.

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

include/deal.II/base/function.h

Public Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

template<int dim, typename RangeNumberType = double> class VectorFunctionFromScalarFunctionObject< dim, RangeNumberType >

Constructor & Destructor Documentation

◆ VectorFunctionFromScalarFunctionObject()

Member Function Documentation

◆ value()

◆ vector_value()

Member Data Documentation

◆ function_object

◆ selected_component

template<int dim, typename RangeNumberType = double>
class VectorFunctionFromScalarFunctionObject< dim, RangeNumberType >