OperatorForceStress Namespace Reference

Classes
struct	OrbitalQuantumNumbers
	Structure to hold orbital quantum numbers. More...

Functions
void	finalize_force_stress (bool cal_force, bool cal_stress, const UnitCell *ucell, const std::vector< double > &stress_tmp, ModuleBase::matrix &force, ModuleBase::matrix &stress, double force_factor=2.0, double stress_factor=2.0)
	Finalize force and stress calculations with MPI reduction and post-processing.
void	setup_step_trace (int npol, int col_size, std::vector< int > &step_trace)
	Setup step_trace array for handling npol (spin polarization)
OrbitalQuantumNumbers	get_orbital_qn (const Atom &atom, int iw)
	Extract orbital quantum numbers from atom and orbital index.
template<typename T >
double	get_real_part (const T &val)
	Helper function to extract real part from complex or real values.
template<>
double	get_real_part< double > (const double &val)
void	rearrange_stress_matrix (ModuleBase::matrix &stress)
	Rearrange stress from 6-component vector to 3x3 matrix format.
template<typename TK , typename TR , typename IntegralFunc , int ForceSign, int StressSign>
void	cal_force_stress_2center (const bool cal_force, const bool cal_stress, const hamilt::HContainer< double > *dmR, const UnitCell *ucell, const Grid_Driver *gridD, const std::vector< double > &orb_cutoff, const Parallel_Orbitals *paraV, IntegralFunc &integral_calculator, ModuleBase::matrix &force, ModuleBase::matrix &stress)
	Template function for calculating force and stress from 2-center integrals.

Function Documentation

cal_force_stress_2center()

template<typename TK , typename TR , typename IntegralFunc , int ForceSign, int StressSign>

void OperatorForceStress::cal_force_stress_2center	(	const bool	cal_force,
		const bool	cal_stress,
		const hamilt::HContainer< double > *	dmR,
		const UnitCell *	ucell,
		const Grid_Driver *	gridD,
		const std::vector< double > &	orb_cutoff,
		const Parallel_Orbitals *	paraV,
		IntegralFunc &	integral_calculator,
		ModuleBase::matrix &	force,
		ModuleBase::matrix &	stress
	)

Template function for calculating force and stress from 2-center integrals.

This template unifies the force/stress calculation pattern for operators that use 2-center integrals (e.g., overlap, kinetic energy). The sign conventions for force and stress are controlled by template parameters to avoid runtime overhead.

Template Parameters

TK	Type for k-space matrices (double or std::complex<double>)
TR	Type for real-space matrices (typically double)
IntegralFunc	Functor type for calculating integrals
ForceSign	Sign convention for force (+1 or -1)
StressSign	Sign convention for stress (+1 or -1)

Parameters

cal_force	Whether to calculate forces
cal_stress	Whether to calculate stress
dmR	Density matrix in real space
ucell	Unit cell containing atomic structure
gridD	Grid driver for finding adjacent atoms
orb_cutoff	Orbital cutoff radii for each atom type
paraV	Parallel orbital distribution information
integral_calculator	Functor that calculates integral and its derivatives
force	Output force matrix (natom x 3)
stress	Output stress matrix (3 x 3)

Here is the call graph for this function:

Here is the caller graph for this function:

finalize_force_stress()

void OperatorForceStress::finalize_force_stress	(	bool	cal_force,
		bool	cal_stress,
		const UnitCell *	ucell,
		const std::vector< double > &	stress_tmp,
		ModuleBase::matrix &	force,
		ModuleBase::matrix &	stress,
		double	force_factor = 2.0,
		double	stress_factor = 2.0
	)

Finalize force and stress calculations with MPI reduction and post-processing.

Performs:

1. MPI reduction of force and stress across all processes
2. Apply force_factor (typically 2.0 for Hermitian matrices)
3. Apply stress weight (lat0/omega) and stress_factor
4. Rearrange stress matrix to 3x3 format

Parameters

cal_force	Whether force calculation is enabled
cal_stress	Whether stress calculation is enabled
ucell	Unit cell containing lattice parameters
stress_tmp	Temporary 6-component stress vector
force	Force matrix to finalize
stress	Stress matrix to finalize
force_factor	Multiplicative factor for force (default: 2.0 for Hermitian)
stress_factor	Multiplicative factor for stress (default: 2.0 for Hermitian)

Here is the call graph for this function:

Here is the caller graph for this function:

get_orbital_qn()

OrbitalQuantumNumbers OperatorForceStress::get_orbital_qn ( const Atom &  atom, int  iw  )

inline

Extract orbital quantum numbers from atom and orbital index.

Parameters

atom	Atom object containing orbital information
iw	Orbital index within the atom

Returns

OrbitalQuantumNumbers structure with L, N, m, M values

Here is the caller graph for this function:

get_real_part()

template<typename T >

double OperatorForceStress::get_real_part ( const T &  val )

inline

Helper function to extract real part from complex or real values.

Template specialization handles both std::complex<T> and double types

get_real_part< double >()

template<>

double OperatorForceStress::get_real_part< double > ( const double &  val )

inline

rearrange_stress_matrix()

void OperatorForceStress::rearrange_stress_matrix ( ModuleBase::matrix &  stress )

inline

Rearrange stress from 6-component vector to 3x3 matrix format.

Input format: [xx, xy, xz, yy, yz, zz] Output format: 3x3 matrix with proper indexing

Parameters

stress

Matrix to rearrange (must be at least 3x3)

Here is the caller graph for this function:

setup_step_trace()

void OperatorForceStress::setup_step_trace ( int  npol, int  col_size, std::vector< int > &  step_trace  )

inline

Setup step_trace array for handling npol (spin polarization)

For npol=1 (non-spin-polarized): step_trace = {0} For npol=2 (spin-polarized): step_trace = {0, 1, col_size, col_size+1}

Parameters

npol	Number of spin polarizations (1 or 2)
col_size	Number of columns in the density matrix block
step_trace	Output vector to store step trace values

Here is the caller graph for this function: