FFTmap_p1: low level P1 map used for calculating FFTs. More...

#include <fftmap.h>

Inheritance diagram for clipper::FFTmap_p1:

Public Member Functions
	FFTmap_p1 ()
	Null constructor.
	FFTmap_p1 (const FFTmap_p1 &other)
	Copy constructor.
	FFTmap_p1 (const Grid_sampling &grid_sam, const FFTtype type=Default)
	Constructor: takes grid.
const FFTmap_p1 &	operator= (const FFTmap_p1 &other)
	Assignment operator.
void	init (const Grid_sampling &grid_sam, const FFTtype type=Default)
	initialiser: takes grid
void	reset ()
	Reset.
const Grid_sampling &	grid_real () const
	Return real space grid.
const Grid &	grid_reci () const
	Return reciprocal space grid (i.e. half real grid + 1 section).
bool	uniq_reci (const Coord_grid &c) const
	Test whether a coordinate is in the valid part of the recip. grid.
void	fft_h_to_x (const ftype &scale)
	Transform to real space.
void	fft_x_to_h (const ftype &scale)
	Transform to reciprocal space.
std::complex< ffttype >	get_hkl (const HKL &hkl) const
	get reciprocal space data: slow form with hemisphere check
void	set_hkl (const HKL &hkl, const std::complex< ffttype > &f)
	set reciprocal space data: slow form with hemisphere check
const std::complex< ffttype > &	cplx_data (const Coord_grid &c) const
	get reciprocal space data
std::complex< ffttype > &	cplx_data (const Coord_grid &c)
	set reciprocal space data
const ffttype &	real_data (const Coord_grid &c) const
	get real space data
ffttype &	real_data (const Coord_grid &c)
	set real space data
void	debug () const
Static Public Member Functions
static FFTtype &	default_type ()
	set/get default optimisation type
Protected Types
enum	FFTmode { NONE, RECI, REAL, OTHER }
Protected Member Functions
const FFTmap_p1 &	copy (const FFTmap_p1 &other)
	copy function
Protected Attributes
FFTmode	mode
	real or reciprocal space?
FFTtype	type_
	optimisation options
Grid_sampling	grid_sam_
	unit cell grid
Grid	grid_reci_
	reciprocal space grid
Grid	grid_real_
	real space grid
Grid	grid_half_
	half grid (for marking unique)
Matrix< char >	req_kl
Matrix< char >	req_uv
	reci section lookup
std::vector< char >	req_l
std::vector< char >	req_u
	real section lookup
std::vector< ffttype >	datavec
	vector for the data
ffttype *	data_r
	pointer to real data
std::complex< ffttype > *	data_c
	pointer to complex data
Static Protected Attributes
static FFTtype	default_type_ = FFTmap_base::Estimate
	default optimisation options

Detailed Description

FFTmap_p1: low level P1 map used for calculating FFTs.

This is a pure real P1 map, with an extra section in reciprocal space to allow generation of the full set of resiprocal space magnitudes. Access is by Coord_grid in both spaces, and indices must be non-negative and in range. The first and last sections along the half-length direction only have half the elements stored, the contents of the other half is ignored.

Constructor & Destructor Documentation

clipper::FFTmap_p1::FFTmap_p1 ( )

Null constructor.

For later initialisation: see init()

clipper::FFTmap_p1::FFTmap_p1	(	const Grid_sampling &	grid_sam,
		const FFTtype	type = `Default`
	)

Constructor: takes grid.

Construct an FFTmap_p1 for a given spacegroup, cell, and grid. The map values are initialised to zero.

The FFTmap_p1 is initially in neither real nor reciprocal spce, however as soon as one of the 'set' methods is called, it will be defined as in either real or reciprocal space until the next fft.

Parameters:

grid_sam	The grid sampling of the unit cell.
type	Can be FFTmap_p1::Measure, FFTmap_p1::Estimate. Measure performs slow precalculation (first time only) to get faster FFT.

References init().

Member Function Documentation

void clipper::FFTmap_p1::init	(	const Grid_sampling &	grid_sam,
		const FFTtype	type = `Default`
	)

initialiser: takes grid

Initialise an FFTmap_p1 for a given spacegroup, cell, and grid. The map values are initialised to zero.

The FFTmap_p1 is initially in neither real nor reciprocal spce, however as soon as one of the 'set' methods is called, it will be defined as in either real or reciprocal space until the next fft.

Parameters:

grid_sam	The grid sampling of the unit cell.
type	Can be FFTmap_p1::Measure, FFTmap_p1::Estimate. Measure performs slow precalculation (first time only) to get faster FFT.

References data_c, data_r, datavec, default_type(), grid_half_, grid_real_, grid_reci_, grid_sam_, mode, clipper::Grid::nu(), clipper::Grid_sampling::nu(), clipper::Grid::nv(), clipper::Grid_sampling::nv(), clipper::Grid::nw(), clipper::Grid_sampling::nw(), clipper::Grid::size(), and type_.

Referenced by FFTmap_p1().

void clipper::FFTmap_p1::reset ( )

Reset.

Reset the space and zero all the data, if necessary.

Reimplemented in clipper::FFTmap.

References datavec, and mode.

const Grid_sampling & clipper::FFTmap_p1::grid_real ( ) const [inline]

Return real space grid.

Returns:: The grid sampling of the real space grid.

References grid_sam_.

Referenced by clipper::FFTmap::get_real_data(), and clipper::FFTmap::grid_sampling().

const Grid & clipper::FFTmap_p1::grid_reci ( ) const [inline]

Return reciprocal space grid (i.e. half real grid + 1 section).

The reciprocal grid is half-length, plus one section, in the w direction. The remainder of the grid may be generated by Hermitian symmetry. When accessing data with reci_data, the coordinate should always be in this grid. Some points in this grid are redundent, see FFTmap_p1::uniq_reci().

Returns:: The reciprocal grid.

References grid_reci_.

bool clipper::FFTmap_p1::uniq_reci ( const Coord_grid & c ) const [inline]

Test whether a coordinate is in the valid part of the recip. grid.

The w=0 and w=nw/2 sections contain some duplicated points related by a cetre of symmetry. On of these is considered to be significant, and the other redundent. This function returns 'true' for the significant point.

Note:: For some calculations it may be quicker to set the whole grid than call this function for every coordinate.

Parameters:

c	The coordinate to test. Must be in grid_reci().

Returns:: true if the coordinate is for a significant point.

References grid_half_, clipper::Grid::nu(), clipper::Grid::nv(), clipper::Grid::nw(), clipper::Coord_grid::u(), clipper::Coord_grid::v(), and clipper::Coord_grid::w().

void clipper::FFTmap_p1::fft_h_to_x ( const ftype & scale )

Transform to real space.

The data is transformed from recirocal to real space. If the FFTmap_p1 is already in real space, no action is taken.

Parameters:

Scale factor to apply (normally 1/cell_volume).

References data_c, grid_reci_, grid_sam_, clipper::Mutex::lock(), mode, clipper::FFTmap_base::mutex, clipper::Grid_sampling::nu(), clipper::Grid_sampling::nv(), clipper::Grid_sampling::nw(), clipper::Grid::size(), type_, and clipper::Mutex::unlock().

Referenced by clipper::Xmap< T >::fft_from().

void clipper::FFTmap_p1::fft_x_to_h ( const ftype & scale )

Transform to reciprocal space.

The data is transformed from real to recirocal space. If the FFTmap_p1 is already in reciproal space, no action is taken.

Parameters:

Scale factor to apply (in addition to 1/N_grid factor) (normally cell_volume).

References data_c, data_r, grid_reci_, grid_sam_, clipper::Mutex::lock(), mode, clipper::FFTmap_base::mutex, clipper::Grid_sampling::nu(), clipper::Grid_sampling::nv(), clipper::Grid_sampling::nw(), clipper::Grid::size(), clipper::Grid_sampling::size(), type_, and clipper::Mutex::unlock().

Referenced by clipper::Xmap< T >::fft_to().

std::complex< ffttype > clipper::FFTmap_p1::get_hkl ( const HKL & hkl ) const

get reciprocal space data: slow form with hemisphere check

This form returns the data for an HKL. The HKL is converted into a grid reference, and the data, or if necessary the conjugate of the opposite, is returned.

Parameters:

hkl	The HKL of the data.

References cplx_data(), grid_reci_, grid_sam_, clipper::Grid_sampling::nu(), clipper::Grid_sampling::nv(), clipper::Grid_sampling::nw(), clipper::Grid::nw(), clipper::Coord_grid::u(), clipper::Coord_grid::unit(), clipper::Coord_grid::v(), and clipper::Coord_grid::w().

Referenced by clipper::Xmap< T >::fft_to(), and clipper::FFTmap::get_recip_data().

void clipper::FFTmap_p1::set_hkl	(	const HKL &	hkl,
		const std::complex< ffttype > &	f
	)

set reciprocal space data: slow form with hemisphere check

This form returns the data for an HKL. The HKL is converted into a grid reference, and the data, and if necessary the conjugate of the opposite, is set.

Parameters:

hkl	The HKL of the data.

References cplx_data(), grid_reci_, grid_sam_, clipper::Grid::nw(), clipper::Coord_grid::unit(), and clipper::Coord_grid::w().

Referenced by clipper::Xmap< T >::fft_from(), and clipper::FFTmap::set_recip_data().

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

fftmap.h
fftmap.cpp

Public Member Functions

Static Public Member Functions

Protected Types

Protected Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation