LookupTable Class Reference

The particle (bead) lookup table. More...

#include <lookuptable.h>

Collaboration diagram for LookupTable:

Public Member Functions
	LookupTable (const Container *, const int, const int)
	Initilialize the nearest neighbor lookup table. More...
	~LookupTable ()
	Free all blitz arrays.
iVec	getNumNNGrid ()
	Return the number of NN grid boxes.
int	getTotNumGridBoxes ()
	Return the total number of grid boxes.
void	updateInteractionList (const Path &, const beadLocator &)
	Update the NN lookup table and the array of beadLocators containing all beads which 'interact' with the supplied bead1.
void	updateFullInteractionList (const beadLocator &, const int)
	Fill up the fullBeadList array with a list of beads in the same grid box as the supplied beadIndex and its nearest neighbors at the supplied time slice.
void	updateFullInteractionList (const int, const int)
	Fill up the fullBeadList array with a list of beads in the supplied grid box indexed by its number and all its nearest neighbors at the supplied time slice.
void	updateGrid (const Path &)
	We update the full nearest neighbor grid by filling up all data arrays at all time slices.
void	updateGrid (const Array< dVec, 1 > &)
	Update the full nearest neighbor for a set of fixed particles, which are never updated and have the same position at all time slices.
void	printGrid ()
	Print the NN Lookup table.
void	delBead (const beadLocator &)
	Remove a single bead from the NN grid.
void	addBead (const beadLocator &, const dVec &)
	Add a single bead to the NN grid and position pos.
void	updateBead (const beadLocator &, const dVec &)
	Update the NN grid with a new bead position.
iVec	gridIndex (const dVec &)
	Given a particle position, return the grid index for the nearest neighbor lookup table.
int	gridNumber (const dVec &)
	Given a particle position, return the grid number for the nearest neighbor lookup table.
iVec	gridIndex (int)
	Given the number of a grid box, returns its coordinates as a NDIM-vector.
int	gridNumber (const iVec &)
	Given the grid index of a box, return its grid number.
void	resizeList (int _numParticles)
	Resize the bead and grid lists.
bool	gridNeighbors (const beadLocator &, const beadLocator &)
	Given two beadIndices, determine if the beads lie in neighboring grid boxes.
bool	gridShare (const beadLocator &bead1, const beadLocator &bead2)
	Determine if two beads are in the same grid box.

Data Fields
const Container *	boxPtr
	The simulation cell.
int	numUniqueNN
	The number of unique nearest neighbors of each box.
int	numNN
	The total number of nearest neighbors of each box.
Array< beadLocator, 1 >	beadList
	The cutoff dynamic list of interacting beads.
Array< beadLocator, 1 >	fullBeadList
	The full dynamic list of interacting beads.
Array< dVec, 1 >	beadSep
	The separation between beads.
int	numBeads
	The cutoff number of active beads in beadList;.
int	fullNumBeads
	The full number of active beads in beadList;.

Detailed Description

The particle (bead) lookup table.

Holds the lookup table and methods for finding where in the simulation cell a particle is located, and which particles are close enough to interact. Accomplishes this by partitioning the simulation cell and storing the box at ever time slice where a bead is located.

Definition at line 29 of file lookuptable.h.

Constructor & Destructor Documentation

LookupTable()

LookupTable::LookupTable	(	const Container *	_boxPtr,
		const int	_numLookupTimeSlices,
		const int	_numParticles
	)

Initilialize the nearest neighbor lookup table.

We partition the simulation cell into a grid of boxes whose edge length is defined by the global potential cutoff radius rc. All date structures are initialized to be empty. We must call an updateBeads method externally in order to place the worldlines in the lookup table.

Definition at line 26 of file lookuptable.cpp.

                                 : 
    boxPtr(_boxPtr),
    numLookupTimeSlices(_numLookupTimeSlices)
{
    /* Setup the nearest neighbor grid list */
    setupNNGrid();
 
    /* We begin with the assumption of evenly distributed particles, therefore
     * there could be numLabels in each cell, allowing for some breathing room */
    for (int i = 0; i < NDIM; i++) 
        hashSize[i] = numNNGrid[i];
    hashSize[NDIM] = numLookupTimeSlices;
    hashSize[NDIM+1] = static_cast<int>(_numParticles/totNumGridBoxes) + 5;
 
    /* Resize and initialize the main hash array */
    hash.resize(hashSize);
    hash = XXX;
 
    /* Resize and initialize the grid and bead label and list arrays */
    resizeList(_numParticles);
    grid = XXX;
    beadLabel= XXX;
    beadList = XXX;
    fullBeadList = XXX;
    beadSep = 0.0;
 
    /* Initialize the cutoff^2 */
    rc2 = constants()->rc2();
}

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

• include/lookuptable.h
• src/lookuptable.cpp