sirius::fft::Grid Class Reference

Helper class to create FFT grids of given sizes and compute indices in space- and frequency domains. More...

#include <fft3d_grid.hpp>

Inherits std::array< int, 3 >.

Public Member Functions
	Grid ()
	Default constructor. More...
	Grid (std::array< int, 3 > initial_dims__)
	Create FFT grid with initial dimensions. More...
const std::pair< int, int > &	limits (int idim__) const
	Limits of a given dimension. More...
int	num_points () const
	Total size of the FFT grid. More...
template<int d>
int	coord_by_freq (int i__) const
	Get coordinate in range [0, N_d) by the frequency index. More...
std::array< int, 3 >	coord_by_freq (int i0__, int i1__, int i2__) const
	Return {x, y, z} coordinates by frequency indices. More...
template<int d>
int	freq_by_coord (int x__) const
	Get frequency by coordinate. More...
std::array< int, 3 >	freq_by_coord (int x__, int y__, int z__) const
	Return 3d vector of frequencies corresponding to {x, y, z} position in the FFT buffer. More...
int	index_by_coord (int x__, int y__, int z__) const
	Linear index inside FFT buffer by grid coordinates. More...
int	index_by_freq (int i0__, int i1__, int i2__) const
	Return linear index of a plane-wave harmonic with fractional coordinates (i0, i1, i2) inside FFT buffer. More...

Private Member Functions
int	find_grid_size (int n)
	Find smallest optimal grid size starting from n. More...
void	find_grid_size (std::array< int, 3 > initial_dims__)
	Find grid sizes and limits for all three dimensions. More...

Private Attributes
std::array< std::pair< int, int >, 3 >	grid_limits_
	Reciprocal space range. More...

Detailed Description

Helper class to create FFT grids of given sizes and compute indices in space- and frequency domains.

Definition at line 37 of file fft3d_grid.hpp.

Constructor & Destructor Documentation

Grid() [1/2]

sirius::fft::Grid::Grid ( )

inline

Default constructor.

Definition at line 91 of file fft3d_grid.hpp.

Grid() [2/2]

sirius::fft::Grid::Grid ( std::array< int, 3 >  initial_dims__ )

inline

Create FFT grid with initial dimensions.

Definition at line 96 of file fft3d_grid.hpp.

Member Function Documentation

find_grid_size() [1/2]

int sirius::fft::Grid::find_grid_size ( int  n )

inlineprivate

Find smallest optimal grid size starting from n.

Definition at line 44 of file fft3d_grid.hpp.

find_grid_size() [2/2]

void sirius::fft::Grid::find_grid_size ( std::array< int, 3 >  initial_dims__ )

inlineprivate

Find grid sizes and limits for all three dimensions.

Definition at line 62 of file fft3d_grid.hpp.

limits()

const std::pair< int, int > & sirius::fft::Grid::limits ( int  idim__ ) const

inline

Limits of a given dimension.

Definition at line 102 of file fft3d_grid.hpp.

num_points()

int sirius::fft::Grid::num_points ( ) const

inline

Total size of the FFT grid.

Definition at line 109 of file fft3d_grid.hpp.

coord_by_freq() [1/2]

template<int d>

int sirius::fft::Grid::coord_by_freq ( int  i__ ) const

inline

Get coordinate in range [0, N_d) by the frequency index.

Definition at line 116 of file fft3d_grid.hpp.

coord_by_freq() [2/2]

std::array< int, 3 > sirius::fft::Grid::coord_by_freq ( int  i0__, int  i1__, int  i2__  ) const

inline

Return {x, y, z} coordinates by frequency indices.

Definition at line 125 of file fft3d_grid.hpp.

freq_by_coord() [1/2]

template<int d>

int sirius::fft::Grid::freq_by_coord ( int  x__ ) const

inline

Get frequency by coordinate.

Definition at line 132 of file fft3d_grid.hpp.

freq_by_coord() [2/2]

std::array< int, 3 > sirius::fft::Grid::freq_by_coord ( int  x__, int  y__, int  z__  ) const

inline

Return 3d vector of frequencies corresponding to {x, y, z} position in the FFT buffer.

Definition at line 141 of file fft3d_grid.hpp.

index_by_coord()

int sirius::fft::Grid::index_by_coord ( int  x__, int  y__, int  z__  ) const

inline

Linear index inside FFT buffer by grid coordinates.

Definition at line 147 of file fft3d_grid.hpp.

index_by_freq()

int sirius::fft::Grid::index_by_freq ( int  i0__, int  i1__, int  i2__  ) const

inline

Return linear index of a plane-wave harmonic with fractional coordinates (i0, i1, i2) inside FFT buffer.

Definition at line 153 of file fft3d_grid.hpp.

Member Data Documentation

grid_limits_

std::array<std::pair<int, int>, 3> sirius::fft::Grid::grid_limits_

private

Reciprocal space range.

Definition at line 41 of file fft3d_grid.hpp.

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

• fft3d_grid.hpp