BackTransformedDiagnostic class handles the back-transformation of data when running simulations in a boosted frame of reference to the lab-frame. Because of the relativity of simultaneity, events that are synchronized in the simulation boosted frame are not synchronized in the lab frame. Thus, at a given t_boost, we must write slices of back-transformed data to multiple output files, each one corresponding to a given time in the lab frame. The member function writeLabFrameData() orchestrates the operations required to Lorentz-transform data from boosted-frame to lab-frame and store them in the LabFrameDiag class, which writes out the field and particle data to the output directory. The functions Flush() and writeLabFrameData() are called at the end of the simulation and when the the buffer for data storage is full, respectively. The particle data is collected and written only if particle.do_back_transformed_diagnostics = 1. More...

#include <BackTransformedDiagnostic.H>

Public Member Functions
	BackTransformedDiagnostic (amrex::Real zmin_lab, amrex::Real zmax_lab, amrex::Real v_window_lab, amrex::Real dt_snapshots_lab, int N_snapshots, amrex::Real dt_slice_snapshots_lab, int N_slice_snapshots, amrex::Real gamma_boost, amrex::Real t_boost, amrex::Real dt_boost, int boost_direction, const amrex::Geometry &geom, amrex::RealBox &slice_realbox, amrex::Real particle_slice_width_lab)

void	Flush (const amrex::Geometry &geom)

void	writeLabFrameData (const amrex::MultiFab *cell_centered_data, const MultiParticleContainer &mypc, const amrex::Geometry &geom, const amrex::Real t_boost, const amrex::Real dt)
	The order of operations performed in writeLabFrameData is as follows : More...

void	writeMetaData ()
	The metadata containg information on t_boost, num_snapshots, and Lorentz parameters. More...

Private Member Functions
void	writeParticleData (const WarpXParticleContainer::DiagnosticParticleData &pdata, const std::string &name, const int i_lab)

Private Attributes
amrex::Real	m_gamma_boost_

amrex::Real	m_inv_gamma_boost_

amrex::Real	m_beta_boost_

amrex::Real	m_inv_beta_boost_

amrex::Real	m_dz_lab_

amrex::Real	m_inv_dz_lab_

amrex::Real	m_dt_snapshots_lab_

amrex::Real	m_dt_boost_

int	m_N_snapshots_

int	m_boost_direction_

int	m_N_slice_snapshots_

amrex::Real	m_dt_slice_snapshots_lab_

amrex::Real	m_particle_slice_width_lab_

int	m_num_buffer_ = 256

int	m_max_box_size_ = 256

std::vector< std::unique_ptr< LabFrameDiag > >	m_LabFrameDiags_

std::map< std::string, int >	m_possible_fields_to_dump

amrex::Vector< int >	map_actual_fields_to_dump

std::vector< std::string >	m_mesh_field_names

int	m_ncomp_to_dump = 10

Detailed Description

BackTransformedDiagnostic class handles the back-transformation of data when running simulations in a boosted frame of reference to the lab-frame. Because of the relativity of simultaneity, events that are synchronized in the simulation boosted frame are not synchronized in the lab frame. Thus, at a given t_boost, we must write slices of back-transformed data to multiple output files, each one corresponding to a given time in the lab frame. The member function writeLabFrameData() orchestrates the operations required to Lorentz-transform data from boosted-frame to lab-frame and store them in the LabFrameDiag class, which writes out the field and particle data to the output directory. The functions Flush() and writeLabFrameData() are called at the end of the simulation and when the the buffer for data storage is full, respectively. The particle data is collected and written only if particle.do_back_transformed_diagnostics = 1.

Constructor & Destructor Documentation

◆ BackTransformedDiagnostic()

BackTransformedDiagnostic::BackTransformedDiagnostic	(	amrex::Real	zmin_lab,
		amrex::Real	zmax_lab,
		amrex::Real	v_window_lab,
		amrex::Real	dt_snapshots_lab,
		int	N_snapshots,
		amrex::Real	dt_slice_snapshots_lab,
		int	N_slice_snapshots,
		amrex::Real	gamma_boost,
		amrex::Real	t_boost,
		amrex::Real	dt_boost,
		int	boost_direction,
		const amrex::Geometry &	geom,
		amrex::RealBox &	slice_realbox,
		amrex::Real	particle_slice_width_lab
	)

Member Function Documentation

◆ Flush()

void BackTransformedDiagnostic::Flush ( const amrex::Geometry & geom )

Flush() is called at the end of the simulation when the buffers that contain back-transformed lab-frame data even if they are not full.

◆ writeLabFrameData()

void BackTransformedDiagnostic::writeLabFrameData	(	const amrex::MultiFab *	cell_centered_data,
		const MultiParticleContainer &	mypc,
		const amrex::Geometry &	geom,
		const amrex::Real	t_boost,
		const amrex::Real	dt
	)

The order of operations performed in writeLabFrameData is as follows :

Loops over the sorted back-transformed diags and for each diag steps 2-7 are performed
Based on t_lab and t_boost, obtain z_lab and z_boost.
Define data_buffer multifab that will store the data in the BT diag.
Define slice multifab at z_index that corresponds to z_boost and getslicedata using cell-centered data at z_index and its distribution map.
Lorentz transform data stored in slice from z_boost,t_Boost to z_lab,t_lab and store in slice multifab.
Generate a temporary slice multifab with distribution map of lab-frame data but at z_boost and ParallelCopy data from the slice multifab to the temporary slice.
Finally, AddDataToBuffer is called where the data from temporary slice is simply copied from tmp_slice(i,j,k_boost) to LabFrameDiagSnapshot(i,j,k_lab) for full BT lab-frame diagnostic OR from tmp_slice(i,j,k_boost) to LabFrameDiagSlice(i,j,k_lab) for the reduced slice diagnostic
Similarly, particles that crossed the z_boost plane are selected and lorentz-transformed to the lab-frame and copied to the full and reduce diagnostic and stored in particle_buffer.

◆ writeMetaData()

void BackTransformedDiagnostic::writeMetaData ( )

The metadata containg information on t_boost, num_snapshots, and Lorentz parameters.

◆ writeParticleData()

void BackTransformedDiagnostic::writeParticleData	(	const WarpXParticleContainer::DiagnosticParticleData &	pdata,
		const std::string &	name,
		const int	i_lab
	)

private

Member Data Documentation

◆ m_beta_boost_

amrex::Real BackTransformedDiagnostic::m_beta_boost_

private

◆ m_boost_direction_

int BackTransformedDiagnostic::m_boost_direction_

private

◆ m_dt_boost_

amrex::Real BackTransformedDiagnostic::m_dt_boost_

private

◆ m_dt_slice_snapshots_lab_

amrex::Real BackTransformedDiagnostic::m_dt_slice_snapshots_lab_

private

◆ m_dt_snapshots_lab_

amrex::Real BackTransformedDiagnostic::m_dt_snapshots_lab_

private

◆ m_dz_lab_

amrex::Real BackTransformedDiagnostic::m_dz_lab_

private

◆ m_gamma_boost_

amrex::Real BackTransformedDiagnostic::m_gamma_boost_

private

◆ m_inv_beta_boost_

amrex::Real BackTransformedDiagnostic::m_inv_beta_boost_

private

◆ m_inv_dz_lab_

amrex::Real BackTransformedDiagnostic::m_inv_dz_lab_

private

◆ m_inv_gamma_boost_

amrex::Real BackTransformedDiagnostic::m_inv_gamma_boost_

private

◆ m_LabFrameDiags_

std::vector<std::unique_ptr<LabFrameDiag> > BackTransformedDiagnostic::m_LabFrameDiags_

private

◆ m_max_box_size_

int BackTransformedDiagnostic::m_max_box_size_ = 256

private

◆ m_mesh_field_names

std::vector<std::string> BackTransformedDiagnostic::m_mesh_field_names

private

Initial value:

= {"Ex", "Ey", "Ez",
                                                 "Bx", "By", "Bz",
                                                 "jx", "jy", "jz", "rho"}

◆ m_N_slice_snapshots_

int BackTransformedDiagnostic::m_N_slice_snapshots_

private

◆ m_N_snapshots_

int BackTransformedDiagnostic::m_N_snapshots_

private

◆ m_ncomp_to_dump

int BackTransformedDiagnostic::m_ncomp_to_dump = 10

private

◆ m_num_buffer_

int BackTransformedDiagnostic::m_num_buffer_ = 256

private

◆ m_particle_slice_width_lab_

amrex::Real BackTransformedDiagnostic::m_particle_slice_width_lab_

private

◆ m_possible_fields_to_dump

std::map<std::string, int> BackTransformedDiagnostic::m_possible_fields_to_dump

private

Initial value:

= {
        {"Ex" , 0},
        {"Ey" , 1},
        {"Ez" , 2},
        {"Bx" , 3},
        {"By" , 4},
        {"Bz" , 5},
        {"jx" , 6},
        {"jy" , 7},
        {"jz" , 8},
        {"rho", 9} }

◆ map_actual_fields_to_dump

amrex::Vector<int> BackTransformedDiagnostic::map_actual_fields_to_dump

private

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

/home/docs/checkouts/readthedocs.org/user_builds/warpx/checkouts/20.10/Source/Diagnostics/BackTransformedDiagnostic.H
/home/docs/checkouts/readthedocs.org/user_builds/warpx/checkouts/20.10/Source/Diagnostics/BackTransformedDiagnostic.cpp

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ BackTransformedDiagnostic()

Member Function Documentation

◆ Flush()

◆ writeLabFrameData()

◆ writeMetaData()

◆ writeParticleData()

Member Data Documentation

◆ m_beta_boost_

◆ m_boost_direction_

◆ m_dt_boost_

◆ m_dt_slice_snapshots_lab_

◆ m_dt_snapshots_lab_

◆ m_dz_lab_

◆ m_gamma_boost_

◆ m_inv_beta_boost_

◆ m_inv_dz_lab_

◆ m_inv_gamma_boost_

◆ m_LabFrameDiags_

◆ m_max_box_size_

◆ m_mesh_field_names

◆ m_N_slice_snapshots_

◆ m_N_snapshots_

◆ m_ncomp_to_dump

◆ m_num_buffer_

◆ m_particle_slice_width_lab_

◆ m_possible_fields_to_dump

◆ map_actual_fields_to_dump