Fft Class Reference

Fft Class Reference#

Reference API: gko::matrix::Fft Class Reference
Reference API

#include <ginkgo/core/matrix/fft.hpp>

Inheritance diagram for gko::matrix::Fft:
[legend]

Public Types

using value_type = std::complex< double >
 
using index_type = int64
 
using transposed_type = Fft
 
- Public Types inherited from gko::EnablePolymorphicAssignment< ConcreteType, ResultType >
using result_type = ResultType
 
- Public Types inherited from gko::ConvertibleTo< ResultType >
using result_type = ResultType
 

Public Member Functions

std::unique_ptr< LinOptranspose () const override
 
std::unique_ptr< LinOpconj_transpose () const override
 
void write (matrix_data< std::complex< float >, int32 > &data) const override
 
void write (matrix_data< std::complex< float >, int64 > &data) const override
 
void write (matrix_data< std::complex< double >, int32 > &data) const override
 
void write (matrix_data< std::complex< double >, int64 > &data) const override
 
dim< 1 > get_fft_size () const
 
bool is_inverse () const
 
- Public Member Functions inherited from gko::EnableLinOp< Fft >
const Fft * apply (ptr_param< const LinOp > b, ptr_param< LinOp > x) const
 
Fft * apply (ptr_param< const LinOp > b, ptr_param< LinOp > x)
 
const Fft * apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x) const
 
Fft * apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x)
 
- Public Member Functions inherited from gko::EnableAbstractPolymorphicObject< AbstractObject, PolymorphicBase >
std::unique_ptr< AbstractObject > create_default (std::shared_ptr< const Executor > exec) const
 
std::unique_ptr< AbstractObject > create_default () const
 
std::unique_ptr< AbstractObject > clone (std::shared_ptr< const Executor > exec) const
 
std::unique_ptr< AbstractObject > clone () const
 
AbstractObject * copy_from (const PolymorphicObject *other)
 
template<typename Derived >
std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, AbstractObject > * copy_from (std::unique_ptr< Derived > &&other)
 
template<typename Derived >
std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, AbstractObject > * copy_from (const std::unique_ptr< Derived > &other)
 
AbstractObject * copy_from (const std::shared_ptr< const PolymorphicObject > &other)
 
AbstractObject * move_from (ptr_param< PolymorphicObject > other)
 
AbstractObject * clear ()
 
- Public Member Functions inherited from gko::PolymorphicObject
PolymorphicObjectoperator= (const PolymorphicObject &)
 
std::unique_ptr< PolymorphicObjectcreate_default (std::shared_ptr< const Executor > exec) const
 
std::unique_ptr< PolymorphicObjectcreate_default () const
 
std::unique_ptr< PolymorphicObjectclone (std::shared_ptr< const Executor > exec) const
 
std::unique_ptr< PolymorphicObjectclone () const
 
PolymorphicObjectcopy_from (const PolymorphicObject *other)
 
template<typename Derived , typename Deleter >
std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, PolymorphicObject > * copy_from (std::unique_ptr< Derived, Deleter > &&other)
 
template<typename Derived , typename Deleter >
std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, PolymorphicObject > * copy_from (const std::unique_ptr< Derived, Deleter > &other)
 
PolymorphicObjectcopy_from (const std::shared_ptr< const PolymorphicObject > &other)
 
PolymorphicObjectmove_from (ptr_param< PolymorphicObject > other)
 
PolymorphicObjectclear ()
 
std::shared_ptr< const Executorget_executor () const noexcept
 
- Public Member Functions inherited from gko::log::EnableLogging< PolymorphicObject >
void add_logger (std::shared_ptr< const Logger > logger) override
 
void remove_logger (const Logger *logger) override
 
void remove_logger (ptr_param< const Logger > logger)
 
const std::vector< std::shared_ptr< const Logger > > & get_loggers () const override
 
void clear_loggers () override
 
- Public Member Functions inherited from gko::log::Loggable
void remove_logger (ptr_param< const Logger > logger)
 
- Public Member Functions inherited from gko::EnablePolymorphicAssignment< ConcreteType, ResultType >
void convert_to (result_type *result) const override
 
void move_to (result_type *result) override
 
- Public Member Functions inherited from gko::ConvertibleTo< ResultType >
void convert_to (ptr_param< result_type > result) const
 
void move_to (ptr_param< result_type > result)
 

Static Public Member Functions

static std::unique_ptr< Fftcreate (std::shared_ptr< const Executor > exec)
 
static std::unique_ptr< Fftcreate (std::shared_ptr< const Executor > exec, size_type size=0, bool inverse=false)
 

Protected Member Functions

 Fft (std::shared_ptr< const Executor > exec, size_type size=0, bool inverse=false)
 
void apply_impl (const LinOp *b, LinOp *x) const override
 
void apply_impl (const LinOp *alpha, const LinOp *b, const LinOp *beta, LinOp *x) const override
 
- Protected Member Functions inherited from gko::EnableLinOp< Fft >
Fft * self () noexcept
 
const Fft * self () const noexcept
 
- Protected Member Functions inherited from gko::EnablePolymorphicObject< ConcreteObject, PolymorphicBase >
std::unique_ptr< PolymorphicObjectcreate_default_impl (std::shared_ptr< const Executor > exec) const override
 
PolymorphicObjectcopy_from_impl (const PolymorphicObject *other) override
 
PolymorphicObjectcopy_from_impl (std::unique_ptr< PolymorphicObject > other) override
 
PolymorphicObjectmove_from_impl (PolymorphicObject *other) override
 
PolymorphicObjectmove_from_impl (std::unique_ptr< PolymorphicObject > other) override
 
PolymorphicObjectclear_impl () override
 
- Protected Member Functions inherited from gko::PolymorphicObject
 PolymorphicObject (std::shared_ptr< const Executor > exec)
 
 PolymorphicObject (const PolymorphicObject &other)
 
- Protected Member Functions inherited from gko::log::EnableLogging< PolymorphicObject >
void log (Params &&... params) const
 

Friends

class EnablePolymorphicObject< Fft, LinOp >
 

Additional Inherited Members

- Protected Attributes inherited from gko::log::EnableLogging< PolymorphicObject >
std::vector< std::shared_ptr< const Logger > > loggers_
 

Detailed Description

This LinOp implements a 1D Fourier matrix using the FFT algorithm.

It implements forward and inverse DFT.

For a power-of-two size n with corresponding root of unity \(\omega = e^{-2\pi i / n}\) for forward DFT and \(\omega = e^{2 \pi i / n}\) for inverse DFT it computes

\[ x_k = \sum_{j=0}^{n-1} \omega^{jk} b_j \]

without normalization factors.

The Reference and OpenMP implementations support only power-of-two input sizes, as they use the Radix-2 algorithm by J. W. Cooley and J. W. Tukey, "An Algorithm for the Machine Calculation of Complex Fourier Series," Mathematics of Computation, vol. 19, no. 90, pp. 297–301, 1965, doi: 10.2307/2003354. The CUDA and HIP implementations use cuSPARSE/hipSPARSE with full support for non-power-of-two input sizes and special optimizations for products of small prime powers.

Member Function Documentation

◆ conj_transpose()

std::unique_ptr< LinOp > gko::matrix::Fft::conj_transpose ( ) const
overridevirtual

Returns a LinOp representing the conjugate transpose of the Transposable object.

Returns
a pointer to the new conjugate transposed object

Implements gko::Transposable.

◆ create() [1/2]

static std::unique_ptr< Fft > gko::matrix::Fft::create ( std::shared_ptr< const Executor exec)
static

Creates an empty Fourier matrix.

Parameters
execExecutor associated to the matrix
Returns
A smart pointer to the newly created matrix.

◆ create() [2/2]

static std::unique_ptr< Fft > gko::matrix::Fft::create ( std::shared_ptr< const Executor exec,
size_type  size = 0,
bool  inverse = false 
)
static

Creates an Fourier matrix with the given dimensions.

Parameters
sizesize of the matrix
inversetrue to compute an inverse DFT instead of a normal DFT
Returns
A smart pointer to the newly created matrix.

◆ transpose()

std::unique_ptr< LinOp > gko::matrix::Fft::transpose ( ) const
overridevirtual

Returns a LinOp representing the transpose of the Transposable object.

Returns
a pointer to the new transposed object

Implements gko::Transposable.


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