DipolarDirectSum Struct Reference

Dipolar all with all and no replica. More...

#include <dipolar_direct_sum.hpp>

Inheritance diagram for DipolarDirectSum:

Collaboration diagram for DipolarDirectSum:

Public Member Functions
	DipolarDirectSum (double prefactor, int n_replicas)
void	on_activation () const
void	on_boxl_change () const
void	on_node_grid_change () const
void	on_periodicity_change () const
void	on_cell_structure_change () const
void	init () const
void	sanity_checks () const
double	long_range_energy (ParticleRange const &particles) const
	Calculate the interaction potential.
void	add_long_range_forces (ParticleRange const &particles) const
	Calculate and add the interaction forces/torques to the particles.
void	dipole_field_at_part (ParticleRange const &particles) const
	Calculate total dipole field of each particle.
Public Member Functions inherited from Dipoles::Actor< DipolarDirectSum >
void	set_prefactor (double new_prefactor)
Public Member Functions inherited from System::Leaf< Class >
void	bind_system (std::shared_ptr< System > const &system)
void	detach_system (std::shared_ptr< System > const &system)

Public Attributes
int	n_replicas
Public Attributes inherited from Dipoles::Actor< DipolarDirectSum >
double	prefactor
	Magnetostatics prefactor.

Additional Inherited Members
Protected Member Functions inherited from System::Leaf< Class >
auto &	get_system ()
auto &	get_system () const
Protected Attributes inherited from System::Leaf< Class >
std::weak_ptr< System >	m_system

Detailed Description

Dipolar all with all and no replica.

Handling of a system of dipoles where no replicas exist. Assumes minimum image convention for those axis in which the system is periodic.

Definition at line 38 of file dipolar_direct_sum.hpp.

Constructor & Destructor Documentation

DipolarDirectSum()

DipolarDirectSum::DipolarDirectSum	(	double	prefactor,
		int	n_replicas
	)

Definition at line 446 of file dipolar_direct_sum.cpp.

References n_replicas, Dipoles::Actor< DipolarDirectSum >::prefactor, and Dipoles::Actor< DipolarDirectSum >::set_prefactor().

Member Function Documentation

add_long_range_forces()

void DipolarDirectSum::add_long_range_forces

(

ParticleRange const &

particles

)

const

Calculate and add the interaction forces/torques to the particles.

This employs a parallel N-square loop over all particle pairs. The computation the partitioned into several steps so that the communication latency can be hidden behinder some local computation:

1. The local particle positions and momenta are packed into one array.
2. The asynchronous distribution of the local arrays to all ranks is started.
3. The interaction for the local pairs is started, here every pair is visited only once, and the force is added to both particles.
4. Wait for the data from the other nodes.
5. Calculate the interaction with the rest of the particles. Here every pair is visited twice (not necessarily on the same rank) so that no reduction of the forces is needed.

Logically this is equivalent to the potential calculation in DipolarDirectSum::long_range_energy, which calculates a naive N-square sum, but has better performance and scaling.

Definition at line 289 of file dipolar_direct_sum.cpp.

References ParticleForce::f, for_each_image(), gather_particle_data(), get_n_cut(), System::Leaf< Class >::get_system(), image_sum(), n_replicas, pair_force(), Dipoles::Actor< DipolarDirectSum >::prefactor, and vector_product().

dipole_field_at_part()

void DipolarDirectSum::dipole_field_at_part

(

ParticleRange const &

particles

)

const

Calculate total dipole field of each particle.

This employs a parallel N-square loop over all particles. Logically this is equivalent to the potential calculation in DipolarDirectSum::long_range_energy, which calculates a naive N-square sum. The difference is summation range, and the kernel calculates the dipole field rather than the energy.

Definition at line 417 of file dipolar_direct_sum.cpp.

References Utils::Array< T, N >::begin(), gather_particle_data(), get_n_cut(), System::Leaf< Class >::get_system(), image_sum(), n_replicas, and Dipoles::Actor< DipolarDirectSum >::prefactor.

init()

void DipolarDirectSum::init ( ) const

inline

Definition at line 47 of file dipolar_direct_sum.hpp.

long_range_energy()

double DipolarDirectSum::long_range_energy

(

ParticleRange const &

particles

)

const

Calculate the interaction potential.

This employs a parallel N-square loop over all particle pairs.

Definition at line 379 of file dipolar_direct_sum.cpp.

References gather_particle_data(), get_n_cut(), System::Leaf< Class >::get_system(), image_sum(), n_replicas, and Dipoles::Actor< DipolarDirectSum >::prefactor.

on_activation()

void DipolarDirectSum::on_activation ( ) const

inline

Definition at line 42 of file dipolar_direct_sum.hpp.

on_boxl_change()

void DipolarDirectSum::on_boxl_change ( ) const

inline

Definition at line 43 of file dipolar_direct_sum.hpp.

on_cell_structure_change()

void DipolarDirectSum::on_cell_structure_change ( ) const

inline

Definition at line 46 of file dipolar_direct_sum.hpp.

on_node_grid_change()

void DipolarDirectSum::on_node_grid_change ( ) const

inline

Definition at line 44 of file dipolar_direct_sum.hpp.

on_periodicity_change()

void DipolarDirectSum::on_periodicity_change ( ) const

inline

Definition at line 45 of file dipolar_direct_sum.hpp.

sanity_checks()

void DipolarDirectSum::sanity_checks ( ) const

inline

Definition at line 48 of file dipolar_direct_sum.hpp.

Member Data Documentation

n_replicas

int DipolarDirectSum::n_replicas

Definition at line 39 of file dipolar_direct_sum.hpp.

Referenced by add_long_range_forces(), DipolarDirectSum(), dipole_field_at_part(), and long_range_energy().

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

• dipolar_direct_sum.hpp
• dipolar_direct_sum.cpp