• clipper::FFTmap_p1

Null constructor.

For later initialisation: see init()

References clipper::Message::message().

Constructor: takes spacegroup, cell, grid.

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

The FFTmap 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:

spacegroup The spacegroup.

cell The cell, used for scaling.

grid_sam The grid sampling of the unit cell.

precalc Perform slow precalculation to get faster FFT. (default: no)

References init(), and clipper::Message::message().

initialiser

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

The FFTmap 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:

spacegroup The spacegroup.

cell The cell, used for scaling.

grid_sam The grid sampling of the unit cell.

precalc Perform slow precalculation to get faster FFT. This adds a penalty of about 4s on Linux for the first FFT of any grid and direction. Subsequent FFTs will be faster. Set to true for programs which will use many FFTs. default: false.

References cell(), cell_, isymop, clipper::Spacegroup::num_symops(), spacegroup(), spacegroup_, and clipper::Spacegroup::symop().

Referenced by FFTmap().

Reset.

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

Reimplemented from clipper::FFTmap_p1.

References clipper::FFTmap_p1::datavec, and clipper::FFTmap_p1::mode.

Referenced by fft_map_to_rfl(), and fft_rfl_to_map().

Transform to real space.

The data is transformed from recirocal to real space. A scale factor of 1/v (where v is the cell volume) is applied. If the FFTmap is already in real space, no action is taken.

References cell(), and clipper::FFTmap_p1::mode.

Referenced by fft_rfl_to_map().

Transform to reciprocal space.

The data is transformed from real to recirocal space. A scale factor of v/n (where v is the cell volume and n the number of grid points) is applied. If the FFTmap is already in reciproal space, no action is taken.

References cell(), and clipper::FFTmap_p1::mode.

Referenced by fft_map_to_rfl().

get reciprocal space data

The data value for the given HKL, or the conjugate of its Friedel opposite if required, is returned. The symmetry related copies of the data are ignored.

Parameters:

rfl The HKL of the data to be returned.

fphi The value, as a magnitude and phase of type ffttype

References clipper::FFTmap_p1::get_hkl(), clipper::Message::message(), and clipper::FFTmap_p1::mode.

Referenced by fft_map_to_rfl().

set reciprocal space data

The data value for the given HKL, or the conjugate of its Friedel opposite if required, is set. All the symmetry related copies of the data, and any Friedel copies in the zero section, are also set.

Parameters:

rfl The HKL of the data to be set.

fphi The value, as a magnitude and phase of type ffttype

References isymop, clipper::Message::message(), clipper::FFTmap_p1::mode, clipper::Spacegroup::num_primops(), clipper::FFTmap_p1::set_hkl(), spacegroup_, clipper::HKL::sym_phase_shift(), clipper::Spacegroup::symop(), and clipper::HKL::transform().

Referenced by fft_rfl_to_map().

get real space data

The data value for the given grid coordinate is returned. Symmetry related copies are ignored.

Parameters:

c The coordinate of the data to be returned.

datum The value of the data.

References clipper::FFTmap_p1::grid_real(), clipper::Message::message(), clipper::FFTmap_p1::mode, clipper::FFTmap_p1::real_data(), and clipper::Coord_grid::unit().

Referenced by fft_rfl_to_map().

set real space data

The data value for the given grid coordinate is set. All the symmetry related copies of the data are also set.

Parameters:

c The coordinate of the data to be set.

datum The value of the data.

References clipper::FFTmap_p1::grid_sam_, isymop, clipper::Message::message(), clipper::FFTmap_p1::mode, clipper::FFTmap_p1::real_data(), clipper::Coord_grid::transform(), and clipper::Coord_grid::unit().

Referenced by fft_map_to_rfl().

get reciprocal space data (No error checking)

No error is produced if the space is wrong.

Parameters:

rfl The HKL of the data to be returned.

Returns:

The value, as magnitude and phase of type ffttype

References clipper::FFTmap_p1::get_hkl().

get real space data (No error checking)

No error is produced if the space is wrong.

Parameters:

c The grid coordinate of the data to be returned.

Returns:

The value, as type ffttype

References clipper::FFTmap_p1::grid_real(), clipper::FFTmap_p1::real_data(), and clipper::Coord_grid::unit().

calculate map-like object from reflection-like object

Fill this FFTmap object from a reflection object, transform it, and fill the given map object from the FFTmap. This will work for any reflection data object which implements a HKL_reference_index, and every map data object which implements a Map_reference_index.

For the results to be sensible, the spacegroup, cell and grids should match. (The map will be zeroed if necessary).

Parameters:

h The source reflection data object.

x The target map object.

References fft_h_to_x(), get_real_data(), reset(), and set_recip_data().

calculate reflection-like object from map-like object

Fill this FFTmap object from a map object, transform it, and fill the given reflection object from the FFTmap. This will work for any reflection data object which implements a HKL_reference_index, and every map data object which implements a Map_reference_index.

For the results to be sensible, the spacegroup, cell and grids should match. (The map will be zeroed if necessary).

Parameters:

x The source map object.

h The target reflection data object.

References fft_x_to_h(), get_recip_data(), reset(), and set_real_data().