amrex::FFT::R2C< T, D, DomainStrategy > Class Template Reference

Parallel Discrete Fourier Transform. More...

#include <AMReX_FFT_R2C.H>

Public Types
using	MF = std::conditional_t< std::is_same_v< T, Real >, MultiFab, FabArray< BaseFab< T > > >
using	cMF = FabArray< BaseFab< GpuComplex< T > > >

Public Member Functions
	R2C (Box const &domain, Info const &info=Info{})
	Constructor. More...
	~R2C ()
	R2C (R2C const &)=delete
	R2C (R2C &&)=delete
R2C &	operator= (R2C const &)=delete
R2C &	operator= (R2C &&)=delete
template<typename F , Direction DIR = D, std::enable_if_t< DIR==Direction::both, int > = 0>
void	forwardThenBackward (MF const &inmf, MF &outmf, F const &post_forward)
	Forward and then backward transform. More...
template<Direction DIR = D, std::enable_if_t< DIR==Direction::forward||DIR==Direction::both, int > = 0>
void	forward (MF const &inmf)
	Forward transform. More...
template<Direction DIR = D, std::enable_if_t< DIR==Direction::forward||DIR==Direction::both, int > = 0>
void	forward (MF const &inmf, cMF &outmf)
	Forward transform. More...
template<Direction DIR = D, std::enable_if_t< DIR==Direction::both, int > = 0>
void	backward (MF &outmf)
	Backward transform. More...
template<Direction DIR = D, std::enable_if_t< DIR==Direction::backward||DIR==Direction::both, int > = 0>
void	backward (cMF const &inmf, MF &outmf)
	Backward transform. More...
T	scalingFactor () const
template<Direction DIR = D, std::enable_if_t< DIR==Direction::forward||DIR==Direction::both, int > = 0>
std::pair< cMF *, IntVect >	getSpectralData ()
	Get the internal spectral data. More...
std::pair< BoxArray, DistributionMapping >	getSpectralDataLayout () const
	Get BoxArray and DistributionMapping for spectral data. More...
template<typename F >
void	post_forward_doit (F const &post_forward)
template<Direction DIR, std::enable_if_t< DIR==Direction::forward||DIR==Direction::both, int > >
std::pair< typename R2C< T, D, S >::cMF *, IntVect >	getSpectralData ()

Private Member Functions
void	backward_doit (MF &outmf, IntVect const &ngout=IntVect(0))

Static Private Member Functions
static std::pair< Plan< T >, Plan< T > >	make_c2c_plans (cMF &inout)

Private Attributes
Plan< T >	m_fft_fwd_x {}
Plan< T >	m_fft_bwd_x {}
Plan< T >	m_fft_fwd_y {}
Plan< T >	m_fft_bwd_y {}
Plan< T >	m_fft_fwd_z {}
Plan< T >	m_fft_bwd_z {}
std::unique_ptr< MultiBlockCommMetaData >	m_cmd_x2y
std::unique_ptr< MultiBlockCommMetaData >	m_cmd_y2x
std::unique_ptr< MultiBlockCommMetaData >	m_cmd_y2z
std::unique_ptr< MultiBlockCommMetaData >	m_cmd_z2y
std::unique_ptr< MultiBlockCommMetaData >	m_cmd_x2z
std::unique_ptr< MultiBlockCommMetaData >	m_cmd_z2x
std::unique_ptr< MultiBlockCommMetaData >	m_cmd_x2z_half
std::unique_ptr< MultiBlockCommMetaData >	m_cmd_z2x_half
Swap01	m_dtos_x2y {}
Swap01	m_dtos_y2x {}
Swap02	m_dtos_y2z {}
Swap02	m_dtos_z2y {}
RotateFwd	m_dtos_x2z {}
RotateBwd	m_dtos_z2x {}
MF	m_rx
cMF	m_cx
cMF	m_cy
cMF	m_cz
std::unique_ptr< char, DataDeleter >	m_data_1
std::unique_ptr< char, DataDeleter >	m_data_2
Box	m_real_domain
Box	m_spectral_domain_x
Box	m_spectral_domain_y
Box	m_spectral_domain_z
Info	m_info
bool	m_slab_decomp = false
bool	m_openbc_half = false

Friends
template<typename U >
class	OpenBCSolver

Detailed Description

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>
class amrex::FFT::R2C< T, D, DomainStrategy >

Parallel Discrete Fourier Transform.

This class supports Fourier transforms between real and complex data. The name R2C indicates that the forward transform converts real data to complex data, while the backward transform converts complex data to real data. It should be noted that both directions of transformation are supported, not just from real to complex. The scaling follows the FFTW convention, where applying the forward transform followed by the backward transform scales the original data by the size of the input array.

For more details, we refer the users to https://amrex-codes.github.io/amrex/docs_html/FFT_Chapter.html.

Member Typedef Documentation

cMF

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

using amrex::FFT::R2C< T, D, DomainStrategy >::cMF = FabArray<BaseFab<GpuComplex<T> > >

MF

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

using amrex::FFT::R2C< T, D, DomainStrategy >::MF = std::conditional_t<std::is_same_v<T,Real>, MultiFab, FabArray<BaseFab<T> > >

Constructor & Destructor Documentation

R2C() [1/3]

template<typename T , Direction D, DomainStrategy S>

amrex::FFT::R2C< T, D, S >::R2C ( Box const &  domain, Info const &  info = Info{}  )

explicit

Constructor.

Parameters

domain	the forward domain (i.e., the domain of the real data)
info	optional information

~R2C()

template<typename T , Direction D, DomainStrategy S>

amrex::FFT::R2C< T, D, S >::~R2C< T, D, S >

R2C() [2/3]

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

amrex::FFT::R2C< T, D, DomainStrategy >::R2C ( R2C< T, D, DomainStrategy > const &  )

delete

R2C() [3/3]

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

amrex::FFT::R2C< T, D, DomainStrategy >::R2C ( R2C< T, D, DomainStrategy > &&  )

delete

Member Function Documentation

backward() [1/2]

template<typename T , Direction D, DomainStrategy S>

template<Direction DIR, std::enable_if_t< DIR==Direction::backward||DIR==Direction::both, int > >

void amrex::FFT::R2C< T, D, S >::backward	(	cMF const &	inmf,
		MF &	outmf
	)

Backward transform.

This function is not available when this class template is instantiated for forward-only transform.

Parameters

inmf	input data in FabArray<BaseFab<GpuComplex<T>>>
outmf	output data in MultiFab or FabArray<BaseFab<float>>

backward() [2/2]

template<typename T , Direction D, DomainStrategy S>

template<Direction DIR, std::enable_if_t< DIR==Direction::both, int > >

void amrex::FFT::R2C< T, D, S >::backward

(

MF &

outmf

)

Backward transform.

This function is available only when this class template is instantiated for transforms in both directions.

Parameters

outmf

output data in MultiFab or FabArray<BaseFab<float>>

backward_doit()

template<typename T , Direction D, DomainStrategy S>

void amrex::FFT::R2C< T, D, S >::backward_doit ( MF &  outmf, IntVect const &  ngout = IntVect(0)  )

private

forward() [1/2]

template<typename T , Direction D, DomainStrategy S>

template<Direction DIR, std::enable_if_t< DIR==Direction::forward||DIR==Direction::both, int > >

void amrex::FFT::R2C< T, D, S >::forward

(

MF const &

inmf

)

Forward transform.

The output is stored in this object's internal data. This function is not available when this class template is instantiated for backward-only transform.

Parameters

inmf	input data in MultiFab or FabArray<BaseFab<float>>

forward() [2/2]

template<typename T , Direction D, DomainStrategy S>

template<Direction DIR, std::enable_if_t< DIR==Direction::forward||DIR==Direction::both, int > >

void amrex::FFT::R2C< T, D, S >::forward	(	MF const &	inmf,
		cMF &	outmf
	)

Forward transform.

This function is not available when this class template is instantiated for backward-only transform.

Parameters

inmf	input data in MultiFab or FabArray<BaseFab<float>>
outmf	output data in FabArray<BaseFab<GpuComplex<T>>>

forwardThenBackward()

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

template<typename F , Direction DIR = D, std::enable_if_t< DIR==Direction::both, int > = 0>

void amrex::FFT::R2C< T, D, DomainStrategy >::forwardThenBackward ( MF const &  inmf, MF &  outmf, F const &  post_forward  )

inline

Forward and then backward transform.

This function is available only when this class template is instantiated for transforms in both directions. It's more efficient than calling the forward function that stores the spectral data in a caller provided container followed by the backward function, because this can avoid parallel communication between the internal data and the caller's data container.

Parameters

inmf	input data in MultiFab or FabArray<BaseFab<float>>
outmf	output data in MultiFab or FabArray<BaseFab<float>>
post_forward	a callable object for processing the post-forward data before the backward transform. Its interface is (int,int,int,GpuComplex<T>&), where the integers are indices in the spectral space, and the reference to the complex number allows for the modification of the spectral data at that location.

getSpectralData() [1/2]

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

template<Direction DIR = D, std::enable_if_t< DIR==Direction::forward||DIR==Direction::both, int > = 0>

std::pair<cMF*,IntVect> amrex::FFT::R2C< T, D, DomainStrategy >::getSpectralData

(

)

Get the internal spectral data.

This function is not available when this class template is instantiated for backward-only transform. For performance reasons, the returned data array does not have the usual ordering of (x,y,z). The order is specified in the second part of the return value.

getSpectralData() [2/2]

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

template<Direction DIR, std::enable_if_t< DIR==Direction::forward||DIR==Direction::both, int > >

std::pair<typename R2C<T,D,S>::cMF *, IntVect> amrex::FFT::R2C< T, D, DomainStrategy >::getSpectralData

(

)

getSpectralDataLayout()

template<typename T , Direction D, DomainStrategy S>

std::pair< BoxArray, DistributionMapping > amrex::FFT::R2C< T, D, S >::getSpectralDataLayout

Get BoxArray and DistributionMapping for spectral data.

The returned BoxArray and DistributionMapping can be used to build FabArray<BaseFab<GpuComplex<T>>> for spectral data. The returned BoxArray has the usual order of (x,y,z).

make_c2c_plans()

template<typename T , Direction D, DomainStrategy S>

std::pair< Plan< T >, Plan< T > > amrex::FFT::R2C< T, D, S >::make_c2c_plans ( cMF &  inout )

staticprivate

operator=() [1/2]

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

R2C& amrex::FFT::R2C< T, D, DomainStrategy >::operator= ( R2C< T, D, DomainStrategy > &&  )

delete

operator=() [2/2]

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

R2C& amrex::FFT::R2C< T, D, DomainStrategy >::operator= ( R2C< T, D, DomainStrategy > const &  )

delete

post_forward_doit()

template<typename T , Direction D, DomainStrategy S>

template<typename F >

void amrex::FFT::R2C< T, D, S >::post_forward_doit

(

F const &

post_forward

)

scalingFactor()

template<typename T , Direction D, DomainStrategy S>

T amrex::FFT::R2C< T, D, S >::scalingFactor

Scaling factor. If the data goes through forward and then backward, the result multiplied by the scaling factor is equal to the original data.

Friends And Related Function Documentation

OpenBCSolver

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

template<typename U >

friend class OpenBCSolver

friend

Member Data Documentation

m_cmd_x2y

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

std::unique_ptr<MultiBlockCommMetaData> amrex::FFT::R2C< T, D, DomainStrategy >::m_cmd_x2y

private

m_cmd_x2z

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

std::unique_ptr<MultiBlockCommMetaData> amrex::FFT::R2C< T, D, DomainStrategy >::m_cmd_x2z

private

m_cmd_x2z_half

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

std::unique_ptr<MultiBlockCommMetaData> amrex::FFT::R2C< T, D, DomainStrategy >::m_cmd_x2z_half

private

m_cmd_y2x

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

std::unique_ptr<MultiBlockCommMetaData> amrex::FFT::R2C< T, D, DomainStrategy >::m_cmd_y2x

private

m_cmd_y2z

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

std::unique_ptr<MultiBlockCommMetaData> amrex::FFT::R2C< T, D, DomainStrategy >::m_cmd_y2z

private

m_cmd_z2x

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

std::unique_ptr<MultiBlockCommMetaData> amrex::FFT::R2C< T, D, DomainStrategy >::m_cmd_z2x

private

m_cmd_z2x_half

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

std::unique_ptr<MultiBlockCommMetaData> amrex::FFT::R2C< T, D, DomainStrategy >::m_cmd_z2x_half

private

m_cmd_z2y

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

std::unique_ptr<MultiBlockCommMetaData> amrex::FFT::R2C< T, D, DomainStrategy >::m_cmd_z2y

private

m_cx

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

cMF amrex::FFT::R2C< T, D, DomainStrategy >::m_cx

private

m_cy

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

cMF amrex::FFT::R2C< T, D, DomainStrategy >::m_cy

private

m_cz

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

cMF amrex::FFT::R2C< T, D, DomainStrategy >::m_cz

private

m_data_1

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

std::unique_ptr<char,DataDeleter> amrex::FFT::R2C< T, D, DomainStrategy >::m_data_1

private

m_data_2

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

std::unique_ptr<char,DataDeleter> amrex::FFT::R2C< T, D, DomainStrategy >::m_data_2

private

m_dtos_x2y

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Swap01 amrex::FFT::R2C< T, D, DomainStrategy >::m_dtos_x2y {}

private

m_dtos_x2z

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

RotateFwd amrex::FFT::R2C< T, D, DomainStrategy >::m_dtos_x2z {}

private

m_dtos_y2x

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Swap01 amrex::FFT::R2C< T, D, DomainStrategy >::m_dtos_y2x {}

private

m_dtos_y2z

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Swap02 amrex::FFT::R2C< T, D, DomainStrategy >::m_dtos_y2z {}

private

m_dtos_z2x

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

RotateBwd amrex::FFT::R2C< T, D, DomainStrategy >::m_dtos_z2x {}

private

m_dtos_z2y

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Swap02 amrex::FFT::R2C< T, D, DomainStrategy >::m_dtos_z2y {}

private

m_fft_bwd_x

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Plan<T> amrex::FFT::R2C< T, D, DomainStrategy >::m_fft_bwd_x {}

private

m_fft_bwd_y

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Plan<T> amrex::FFT::R2C< T, D, DomainStrategy >::m_fft_bwd_y {}

private

m_fft_bwd_z

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Plan<T> amrex::FFT::R2C< T, D, DomainStrategy >::m_fft_bwd_z {}

private

m_fft_fwd_x

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Plan<T> amrex::FFT::R2C< T, D, DomainStrategy >::m_fft_fwd_x {}

private

m_fft_fwd_y

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Plan<T> amrex::FFT::R2C< T, D, DomainStrategy >::m_fft_fwd_y {}

private

m_fft_fwd_z

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Plan<T> amrex::FFT::R2C< T, D, DomainStrategy >::m_fft_fwd_z {}

private

m_info

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Info amrex::FFT::R2C< T, D, DomainStrategy >::m_info

private

m_openbc_half

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

bool amrex::FFT::R2C< T, D, DomainStrategy >::m_openbc_half = false

private

m_real_domain

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Box amrex::FFT::R2C< T, D, DomainStrategy >::m_real_domain

private

m_rx

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

MF amrex::FFT::R2C< T, D, DomainStrategy >::m_rx

private

m_slab_decomp

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

bool amrex::FFT::R2C< T, D, DomainStrategy >::m_slab_decomp = false

private

m_spectral_domain_x

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Box amrex::FFT::R2C< T, D, DomainStrategy >::m_spectral_domain_x

private

m_spectral_domain_y

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Box amrex::FFT::R2C< T, D, DomainStrategy >::m_spectral_domain_y

private

m_spectral_domain_z

template<typename T = Real, FFT::Direction D = FFT::Direction::both, FFT::DomainStrategy = FFT::DomainStrategy::slab>

Box amrex::FFT::R2C< T, D, DomainStrategy >::m_spectral_domain_z

private

---

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

• /home/runner/work/amrex/amrex/Src/FFT/AMReX_FFT_R2C.H