#include <CellSnapshot.hpp>

Inheritance diagram for CellSnapshot:

Public Member Functions
double	density (int m) const override

double	density (Position bfr) const override

Box	extent () const override

Position	generatePosition () const override

Position	generatePosition (int m) const override

void	getEntities (EntityCollection &entities, Position bfr) const override

void	getEntities (EntityCollection &entities, Position bfr, Direction bfk) const override

double	mass () const override

int	numEntities () const override

Position	position (int m) const override

void	readAndClose () override

double	volume (int m) const override

Public Member Functions inherited from Snapshot
	Snapshot ()

virtual	~Snapshot ()

double	age (int m) const

double	bias (int m) const

void	close ()

double	currentMass (int m) const

virtual double	density (int m) const =0

virtual double	density (Position bfr) const =0

virtual Box	extent () const =0

virtual Position	generatePosition () const =0

virtual Position	generatePosition (int m) const =0

virtual void	getEntities (EntityCollection &entities, Position bfr) const =0

virtual void	getEntities (EntityCollection &entities, Position bfr, Direction bfk) const =0

bool	hasAge () const

bool	hasBias () const

bool	hasCurrentMass () const

bool	hasInitialMass () const

bool	hasMagneticField () const

bool	hasMetallicity () const

bool	hasParameters () const

bool	hasTemperature () const

bool	hasVelocity () const

bool	hasVelocityDispersion () const

bool	holdsNumber () const

void	importBias ()

void	importBox ()

void	importCurrentMass ()

void	importMagneticField ()

void	importMass ()

void	importMassDensity ()

void	importMetallicity ()

void	importNumber ()

void	importNumberDensity ()

void	importParameters (const vector< SnapshotParameter > &parameters)

void	importPosition ()

void	importSize ()

void	importTemperature ()

void	importVelocity ()

void	importVelocityDispersion ()

double	initialMass (int m) const

Vec	magneticField (int m) const

Vec	magneticField (Position bfr) const

virtual double	mass () const =0

double	metallicity (int m) const

double	metallicity (Position bfr) const

virtual int	numEntities () const =0

void	open (const SimulationItem *item, string filename, string description)

void	parameters (int m, Array &params) const

void	parameters (Position bfr, Array &params) const

virtual Position	position (int m) const =0

virtual void	readAndClose ()

void	setCoordinateSystem (CoordinateSystem coordinateSystem)

void	setMassDensityPolicy (double multiplier, double maxTemperature, bool useMetallicity)

void	setNeedGetEntities ()

double	SigmaX () const

double	SigmaY () const

double	SigmaZ () const

double	temperature (int m) const

double	temperature (Position bfr) const

void	useColumns (string columns)

Vec	velocity (int m) const

Vec	velocity (Position bfr) const

double	velocityDispersion (int m) const

double	volume () const

virtual double	volume (int m) const =0

Protected Member Functions
const Array &	properties (int m) const override

Protected Member Functions inherited from Snapshot
int	ageIndex () const

int	biasIndex () const

int	boxIndex () const

void	calculateDensityAndMass (Array &rhov, Array &cumrhov, double &mass)

int	currentMassIndex () const

int	densityIndex () const

bool	hasMassDensityPolicy () const

TextInFile *	infile ()

int	initialMassIndex () const

Log *	log () const

void	logMassStatistics (int numIgnored, double totalOriginalMass, double totalMetallicMass, double totalEffectiveMass)

int	magneticFieldIndex () const

int	massIndex () const

double	maxTemperature () const

int	metallicityIndex () const

double	multiplier () const

bool	needGetEntities () const

int	numParameters () const

int	parametersIndex () const

int	positionIndex () const

virtual const Array &	properties (int m) const =0

Random *	random () const

void	setContext (const SimulationItem *item)

int	sizeIndex () const

int	temperatureIndex () const

Units *	units () const

bool	useMetallicity () const

bool	useTemperatureCutoff () const

int	velocityDispersionIndex () const

int	velocityIndex () const

Private Member Functions
Box	boxForCell (int m) const

Private Attributes
Array	_cumrhov

double	_mass

vector< Array >	_propv

Array	_rhov

BoxSearch	_search

Additional Inherited Members
Public Types inherited from Snapshot
enum class	CoordinateSystem { CARTESIAN , CYLINDRICAL , SPHERICAL }

Detailed Description

A CellSnapshot object represents the data in a Cartesian mesh-based snapshot imported from a column text file. Each line in the text file represents a cuboidal cell lined up with the coordinate axes, specifying the coordinates of the lower-left and upper-right corners of the cell along with properties such as the density in the cell. The intention is for the cells to define a partition of the spatial domain, and usually they will, however this is not enforced. When two or more cells overlap at a given position, the properties for that position will be taken from the cell that is listed first in the imported file. When no cells overlap a given position, the density at that position is considered to be zero. To avoid thin slices of zero density between cells, the coordinates for common walls or corners in neighboring cells should be identical.

This class is an alternative to the AdaptiveMeshSnapshot class, which requires listing cells in Morton order. This can be hard to accomplish, especially when extracting a particular subdomain from a larger mesh. In contrast, the CellSnapshot class allows cells to be listed in arbitrary order and allows the spatial partition to be imperfect. For example, the outer border of the domain can be ragged, with some cells extending farther out than others.

This class is based on the Snapshot class; it uses the facilities offered there to configure and read the snapshot data, and it implements all functions in the general Snapshot public interface. If the snapshot configuration requires the ability to determine the density at a given spatial position, an effort is made to accelerate the search for the cell containing that position even for a large number of cells.

Member Function Documentation

◆ boxForCell()

Box CellSnapshot::boxForCell ( int m ) const

private

This function returns the bounding box representing the cell with the given index. If the index is out of range, the behavior is undefined.

◆ density() [1/2]

double CellSnapshot::density ( int m ) const

overridevirtual

This function returns the mass density associated with the cell with index m. If no density policy has been set or no mass information is being imported, or if the index is out of range, the behavior is undefined.

Implements Snapshot.

◆ density() [2/2]

double CellSnapshot::density ( Position bfr ) const

overridevirtual

This function returns the mass density of the cell containing the specified point $r$ . If the point is not inside any cell, the function returns zero. If no density policy has been set or no mass information is being imported, the behavior is undefined.

Implements Snapshot.

◆ extent()

Box CellSnapshot::extent ( ) const

overridevirtual

This function returns the bounding box lined up with the coordinate axes surrounding all cells.

Implements Snapshot.

◆ generatePosition() [1/2]

Position CellSnapshot::generatePosition ( ) const

overridevirtual

This function returns a random position within the spatial domain of the snapshot, drawn from the mass density distribution represented by the snapshot. The function first selects a random cell from the discrete probability distribution formed by the respective cell masses, and then generates a random position within that cell. If no density policy has been set or no mass information is being imported, the behavior is undefined.

Implements Snapshot.

◆ generatePosition() [2/2]

Position CellSnapshot::generatePosition ( int m ) const

overridevirtual

This function returns a random position drawn uniformly from the cell with index m. If the index is out of range, the behavior is undefined.

Implements Snapshot.

◆ getEntities() [1/2]

void CellSnapshot::getEntities	(	EntityCollection &	entities,
		Position	bfr
	)		const

overridevirtual

This function sets the specified entity collection to the cell containing the specified point $r$ , or to the empty collection if the point is outside the domain or if there are no cells in the snapshot. If the search data structures were not created, invoking this function causes undefined behavior.

Implements Snapshot.

◆ getEntities() [2/2]

void CellSnapshot::getEntities	(	EntityCollection &	entities,
		Position	bfr,
		Direction	bfk
	)		const

overridevirtual

This function replaces the contents of the specified entity collection by the set of cells that overlap the specified path with starting point $r$ and direction $k$ . The weight of a cell is given by the length of the path segment inside the cell. If the path does not overlap any cells, the collection will be empty. If the search data structures were not created, invoking this function causes undefined behavior.

Implements Snapshot.

◆ mass()

double CellSnapshot::mass ( ) const

overridevirtual

This function returns the total mass represented by the snapshot, in other words the sum of the masses of all cells. If no density policy has been set or no mass information is being imported, the behavior is undefined.

Implements Snapshot.

◆ numEntities()

int CellSnapshot::numEntities ( ) const

overridevirtual

This function returns the number of cells in the snapshot.

Implements Snapshot.

◆ position()

Position CellSnapshot::position ( int m ) const

overridevirtual

This function returns the position of the center of the cell with index m. If the index is out of range, the behavior is undefined.

Implements Snapshot.

◆ properties()

const Array & CellSnapshot::properties ( int m ) const

overrideprotectedvirtual

This function returns a reference to an array containing the imported properties (in column order) for the cell with index $0 \leq m \leq N_{e n t} - 1$ . If the index is out of range, the behavior is undefined.

Implements Snapshot.

◆ readAndClose()

void CellSnapshot::readAndClose ( )

overridevirtual

This function reads the snapshot data from the input file, honoring the options set through the configuration functions, stores the data for later use, and closes the file by calling the base class Snapshot::readAndClose() function.

Cells with an associated temperature above the cutoff temperature (if one has been configured) are assigned a density value of zero, so that they have zero mass regardless of the imported mass/density properties. Note that we cannot simply ignore these cells because an empty cell may overlap and thus hide (a portion of) a nonempty cell later in the list.

The function also logs some statistical information about the import. If the snapshot configuration requires the ability to determine the density at a given spatial position, this function builds a data structure that accelerates the search for the appropriate cell.

Reimplemented from Snapshot.

◆ volume()

double CellSnapshot::volume ( int m ) const

overridevirtual

This function returns the volume of the cell with index m. If the index is out of range, the behavior is undefined.

Implements Snapshot.

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

CellSnapshot.hpp

Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ boxForCell()

◆ density() [1/2]

◆ density() [2/2]

◆ extent()

◆ generatePosition() [1/2]

◆ generatePosition() [2/2]

◆ getEntities() [1/2]

◆ getEntities() [2/2]

◆ mass()

◆ numEntities()

◆ position()

◆ properties()

◆ readAndClose()

◆ volume()