#include <g_vectors_grid.hpp>

Inheritance diagram for q3::GVectorsGrid:

Public Member Functions
	GVectorsGrid ()=default

int	estimate_maximum_plane_waves_per_kpoint (Real energy_cutoff_wavefunction, Real two_pi_over_lattice_parameter_squared) const

int	first_nonzero_g_index () const

const GVector &	g_vector (int index) const

const std::vector< Real > &	g_vector_magnitudes () const

int	g_vector_to_fft_grid_index (const GVector &g_vector) const
	Compute the FFT grid index for a G-vector from its Miller indices.

const std::vector< GVector > &	g_vectors () const

void	generate (const Crystal &crystal_structure, Real energy_cutoff_charge_density, int grid_dimension_1, int grid_dimension_2, int grid_dimension_3, bool is_gamma_only=false, int rank=0, int size=1, int fft_local_start=-1, int fft_local_dimension_1=-1)

int	global_number_of_g_vectors () const

int	grid_dimension_1 () const

bool	is_gamma_only () const

int	local_g_vector_start_index () const

int	local_number_of_g_vectors () const

int	number_of_g_vectors () const

Public Member Functions inherited from q3::ReciprocalSpaceVectorsGrid
	ReciprocalSpaceVectorsGrid ()=default

int	number_of_vectors () const

const ReciprocalSpaceVector &	vector (int index) const

const std::vector< ReciprocalSpaceVector > &	vectors () const

Public Member Functions inherited from q3::PointsGrid
	PointsGrid ()=default

virtual	~PointsGrid ()=default

bool	empty () const

int	number_of_points () const

const WeightedPoint3D &	point (int index) const

const std::vector< WeightedPoint3D > &	points () const

Protected Attributes
int	first_nonzero_g_index_ {}

std::vector< Real >	g_vector_magnitudes_

std::vector< GVector >	g_vectors_

int	global_number_of_g_vectors_ {0}

int	grid_dimension_1_ {}

int	grid_dimension_2_ {}

int	grid_dimension_3_ {}

bool	is_gamma_only_ {false}

int	local_count_ {0}

int	local_start_ {0}

Protected Attributes inherited from q3::ReciprocalSpaceVectorsGrid
std::vector< ReciprocalSpaceVector >	vectors_

Protected Attributes inherited from q3::PointsGrid
std::vector< WeightedPoint3D >	points_

Detailed Description

Definition at line 19 of file g_vectors_grid.hpp.

Constructor & Destructor Documentation

◆ GVectorsGrid()

q3::GVectorsGrid::GVectorsGrid ( )

default

Member Function Documentation

◆ estimate_maximum_plane_waves_per_kpoint()

int q3::GVectorsGrid::estimate_maximum_plane_waves_per_kpoint	(	Real	energy_cutoff_wavefunction,
		Real	two_pi_over_lattice_parameter_squared
	)		const

inline

Definition at line 225 of file g_vectors_grid.hpp.

References q3::math::tolerances::energy_cutoff_rounding_tolerance, g_vector(), g_vectors_, q3::GVector::magnitude_squared, and q3::ReciprocalSpaceVectorsGrid::vector().

Referenced by q3::PlanewaveBasis::generate().

◆ first_nonzero_g_index()

int q3::GVectorsGrid::first_nonzero_g_index ( ) const

inline

Definition at line 212 of file g_vectors_grid.hpp.

References first_nonzero_g_index_.

Referenced by q3::PlanewaveBasis::first_nonzero_g_index(), and q3::ChargeDensityTransformer::rho_g_to_r().

◆ g_vector()

const GVector & q3::GVectorsGrid::g_vector ( int index ) const

inline

Definition at line 208 of file g_vectors_grid.hpp.

References g_vectors_.

Referenced by estimate_maximum_plane_waves_per_kpoint(), g_vector_to_fft_grid_index(), and generate().

◆ g_vector_magnitudes()

const std::vector< Real > & q3::GVectorsGrid::g_vector_magnitudes ( ) const

inline

Definition at line 216 of file g_vectors_grid.hpp.

References g_vector_magnitudes_.

Referenced by q3::PlanewaveBasis::g_vector_magnitudes().

◆ g_vector_to_fft_grid_index()

int q3::GVectorsGrid::g_vector_to_fft_grid_index ( const GVector & g_vector ) const

inline

Compute the FFT grid index for a G-vector from its Miller indices.

Definition at line 167 of file g_vectors_grid.hpp.

References g_vector(), grid_dimension_1_, grid_dimension_2_, grid_dimension_3_, q3::GVector::miller, and q3::ReciprocalSpaceVectorsGrid::vector().

◆ g_vectors()

const std::vector< GVector > & q3::GVectorsGrid::g_vectors ( ) const

inline

Definition at line 204 of file g_vectors_grid.hpp.

References g_vectors_.

Referenced by q3::WavefunctionTransformer::g_to_r(), q3::PlanewaveBasis::g_vectors(), q3::PlanewaveBasis::initialize_kpoint_data(), q3::WavefunctionTransformer::r_to_g(), q3::ChargeDensityTransformer::rho_g_to_r(), q3::ChargeDensityTransformer::rho_r_to_g(), q3::PlaneWaveSelector::select(), and q3::PlanewaveBasis::stick_weights_for_grid().

◆ generate()

void q3::GVectorsGrid::generate	(	const Crystal &	crystal_structure,
		Real	energy_cutoff_charge_density,
		int	grid_dimension_1,
		int	grid_dimension_2,
		int	grid_dimension_3,
		bool	is_gamma_only = `false`,
		int	rank = `0`,
		int	size = `1`,
		int	fft_local_start = `-1`,
		int	fft_local_dimension_1 = `-1`
	)

inline

For gamma-only, keep only the positive half-sphere: index_3 > 0, OR index_3 == 0 && index_2 > 0, OR index_3 == 0 && index_2 == 0 && index_1 >= 0 The half itself is dictated: rho(-G) = conj(rho(G)) for a real density, so one of each +/-G pair is redundant, and G = 0 – its own partner – is kept once, which is why the last key above is >= 0 and not > 0. Which half is free, and this is not the one Quantum ESPRESSO keeps: its rule leads on the FIRST Miller index where this one leads on the third, so the two codes hold mirror-image halves. Read the rule above rather than assume the two lists are interchangeable.

SLAB-BASED PARTITIONING: Each rank owns G-vectors that fall into its FFT slabs. This ensures all G-vectors are local when scattering to/from the FFT grid. Note: This replaces index-based partitioning when FFT slab info is provided.

Overwrite global g_vectors_ with local ones. WARNING: This rank now only knows about its local G-vectors. For dot_product and other collectives, this is fine as long as everyone knows it's a partition.

Definition at line 23 of file g_vectors_grid.hpp.

References q3::math::tolerances::energy_cutoff_rounding_tolerance, first_nonzero_g_index_, q3::GVector::g_cart, g_vector(), g_vector_magnitudes_, g_vectors_, global_number_of_g_vectors_, grid_dimension_1(), grid_dimension_1_, grid_dimension_2_, grid_dimension_3_, is_gamma_only(), is_gamma_only_, local_count_, local_start_, q3::GVector::magnitude_squared, q3::GVector::miller, q3::Crystal::reciprocal_lattice_vectors(), q3::Crystal::two_pi_over_lattice_parameter(), q3::Crystal::two_pi_over_lattice_parameter_squared(), q3::ReciprocalSpaceVectorsGrid::vector(), q3::IntegerVector3D::x, and q3::math::tolerances::zero_vector_magnitude_threshold.