Functions::FourierCosineSum< dim > Class Template Reference

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

Inheritance diagram for Functions::FourierCosineSum< dim >:

Public Member Functions
	FourierCosineSum (const std::vector< Point< dim > > &fourier_coefficients, const std::vector< double > &weights)
virtual double	value (const Point< dim > &p, const unsigned int component=0) const
virtual Tensor< 1, dim >	gradient (const Point< dim > &p, const unsigned int component=0) const
virtual double	laplacian (const Point< dim > &p, const unsigned int component=0) const
Public Member Functions inherited from Function< dim >
	Function (const unsigned int n_components=1, const double initial_time=0.0)
virtual	~Function ()=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 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 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< Number >
	FunctionTime (const Number initial_time=Number(0.0))
virtual	~FunctionTime ()=default
Number	get_time () const
virtual void	set_time (const Number new_time)
virtual void	advance_time (const Number 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 (const char *identifier=nullptr) const
void	unsubscribe (const char *identifier=nullptr) const
unsigned int	n_subscriptions () const
void	list_subscribers () const
template<class Archive >
void	serialize (Archive &ar, const unsigned int version)

Private Attributes
const std::vector< Point< dim > >	fourier_coefficients

Additional Inherited Members
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 >
const unsigned int	n_components
Static Public Attributes inherited from Function< dim >
static const unsigned int	dimension

Detailed Description

template<int dim>
class Functions::FourierCosineSum< dim >

Given a sequence of wavenumber vectors and weights generate a sum of cosine functions. Each wavenumber coefficient is given as a \(d\)-dimensional point \(k\) in Fourier space, and the entire function is then recovered as \(f(x) = \sum_j w_j cos(\sum_i k_i x_i) = Re(\sum_j w_j \exp(i k.x))\).

Author

Wolfgang Bangerth, 2001

Definition at line 786 of file function_lib.h.

Constructor & Destructor Documentation

FourierCosineSum()

template<int dim>

Functions::FourierCosineSum< dim >::FourierCosineSum	(	const std::vector< Point< dim > > &	fourier_coefficients,
		const std::vector< double > &	weights
	)

Constructor. Take the Fourier coefficients in each space direction as argument.

Definition at line 2004 of file function_lib.cc.

Member Function Documentation

value()

template<int dim>

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

virtual

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 >.

Definition at line 2021 of file function_lib.cc.

gradient()

template<int dim>

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

virtual

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

Reimplemented from Function< dim >.

Definition at line 2039 of file function_lib.cc.

laplacian()

template<int dim>

double Functions::FourierCosineSum< dim >::laplacian ( const Point< dim > &  p, const unsigned int  component = 0  ) const

virtual

Compute the Laplacian of a given component at point p.

Reimplemented from Function< dim >.

Definition at line 2057 of file function_lib.cc.

Member Data Documentation

fourier_coefficients

template<int dim>

const std::vector<Point<dim> > Functions::FourierCosineSum< dim >::fourier_coefficients

private

Stored Fourier coefficients and weights.

Definition at line 822 of file function_lib.h.

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

• deal.II/base/function_lib.h
• source/base/function_lib.cc