This container class caches a point set by precomputing and storing all the points locally in an array. More...

Inheritance diagram for umontreal.ssj.hups.CachedPointSet:

Classes
class	CachedPointSetIterator
	This class implements a CachedPointSet iterator which takes the values directly in the array x in which the points are cached, rather than calling CachedPointSet.getCoordinate. More...

Public Member Functions
	CachedPointSet (PointSet p, int fromPoint, int toPoint, int fromDim, int toDim)
	Creates a new PointSet object that contains an array storing the coordinates fromDim (inclusive) to toDim (exclusive) of the points numbered fromPoint (inclusive) to toPoint (exclusive) of p.
	CachedPointSet (PointSet p, int n, int dim)
	Same as `CachedPointSet(p, 0, n, 0, dim)`.
	CachedPointSet (PointSet p)
	Creates a new PointSet object that contains an array storing the points of p.
PointSetIterator	iterator ()
	Constructs and returns a point set iterator that gets the values directly from the cached array.
void	setRandomizeParent (boolean randomizeParent)
	If randomizeParent is true, calls to randomize() will be defered to the parent point set (this is the default); otherwise, the randomize method of the PointSetRandomization instance is invoked with this CachedPointSet instance as its argument.
void	addRandomShift (int d1, int d2, RandomStream stream)
	Generates a random shift, adds it to the contained point set, and re-caches the points.
void	randomize (PointSetRandomization rand)
	Randomizes the underlying point set using rand and re-caches the points.
void	sortByCoordinate (int j)
	Sorts the cached points by increasing order of coordinate j.
void	stripCoordinates (int d)
	Removes the first d coordinates of each cached point.
String	toString ()
	Formats a string that contains information about the point set.
double	getCoordinate (int i, int j)
	Returns \(u_{i,j}\), the coordinate \(j\) of the point \(i\).
PointSet	getParentPointSet ()
	Returns the reference point set that was passed to the constructor.
Public Member Functions inherited from umontreal.ssj.hups.PointSet
int	getDimension ()
	Returns the dimension (number of available coordinates) of the points.
int	getNumPoints ()
	Returns the number of points.
void	addRandomShift (RandomStream stream)
	Same as `addRandomShift(0, dim, stream)`, where dim is the dimension of the point set.
void	addRandomShift (int d1, int d2)
	Refreshes the random shift (generates new uniform values for the random shift coordinates) for coordinates d1 to d2-1, using the saved shiftStream.
void	addRandomShift ()
	Same as `addRandomShift(0, dim)`, where dim is the dimension of the point set.
void	clearRandomShift ()
	Erases the current random shift, if any.
String	formatPoints ()
	Same as invoking `formatPoints(n, d)` with \(n\) and \(d\) equal to the number of points and the dimension of this object, respectively.
String	formatPoints (int n, int d)
	Formats a string that displays the same information as returned by toString, together with the first \(d\) coordinates of the first.
String	formatPoints (PointSetIterator iter)
	Same as invoking `formatPoints(iter, n, d)` with \(n\) and \(d\) equal to the number of points and the dimension, respectively.
String	formatPoints (PointSetIterator iter, int n, int d)
	Same as invoking `formatPoints(n, d)`, but prints the points by calling iter repeatedly.
String	formatPointsBase (int b)
	Similar to `formatPoints()`, but the points coordinates are printed in base \(b\).
String	formatPointsBase (int n, int d, int b)
	Similar to `formatPoints(n, d)`, but the points coordinates are printed in base \(b\).
String	formatPointsBase (PointSetIterator iter, int b)
	Similar to `formatPoints(iter)`, but the points coordinates are printed in base.
String	formatPointsBase (PointSetIterator iter, int n, int d, int b)
	Similar to `formatPoints(iter, n, d)`, but the points coordinates are printed in base \(b\).
String	formatPointsNumbered ()
	Same as invoking `formatPointsNumbered(n, d)` with \(n\) and \(d\) equal to the number of points and the dimension, respectively.
String	formatPointsNumbered (int n, int d)
	Same as invoking `formatPoints(n,d)`, except that the points are numbered.

Protected Member Functions
void	fillCache (int fromDim, int dim)
	Caches the points, skipping fromDim coordinates and taking the next dim ones.

Package Functions
public< T > void	sort (MultiDimSort< T > sort)
	Sorts the cached points (only) with the given.

Additional Inherited Members
Static Public Member Functions inherited from umontreal.ssj.hups.PointSet
static int	getMaxBits ()
	Returns the maximum number of usable bits.
Protected Attributes inherited from umontreal.ssj.hups.PointSet
double	EpsilonHalf = 1.0 / Num.TWOEXP[55]
	To avoid 0 for nextCoordinate when random shifting, we add this to each coordinate.
int	dim = 0
	Dimension of the points.
int	numPoints = 0
	Number of points.
int	dimShift = 0
	Current dimension of the shift.
int	capacityShift = 0
	Number of array elements in the shift vector, always >= dimShift.
double[]	shift
	This is the shift vector as a double[] array, which contains the current random shift in case we apply a random shift modulo 1.
RandomStream	shiftStream
	Stream used to generate the random shifts.
Static Protected Attributes inherited from umontreal.ssj.hups.PointSet
static final int	MAXBITS = 31
	Since Java has no unsigned type, the 32nd bit cannot be used efficiently, so we have only 31 bits.

Detailed Description

This container class caches a point set by precomputing and storing all the points locally in an array.

Its primary usage is for the situations in which the points must be stored explicitly; see, e.g., LatinHypercube,

StratifiedUnitCube, and NestedUniformScambling. Some types of point sets are implemented directly as subclasses of this one, without having a contained point set p. It may also be used to speed up computations when using a small low-dimensional point set more than once.

There is a sort method available to sort the cached points via a umontreal.ssj.util.MultiDimSort, and a stripCoordinates method that remove some coordinates of the cached points. Those methods affect only the array where the points are cached; they have no impact on the (underlying) original point set. The randomize method, on the other hand, randomizes the underlying point set p and re-caches them.

Definition at line 52 of file CachedPointSet.java.

Constructor & Destructor Documentation

◆ CachedPointSet() [1/3]

umontreal.ssj.hups.CachedPointSet.CachedPointSet	(	PointSet	p,
		int	fromPoint,
		int	toPoint,
		int	fromDim,
		int	toDim )

Creates a new PointSet object that contains an array storing the coordinates fromDim (inclusive) to toDim (exclusive) of the points numbered fromPoint (inclusive) to toPoint (exclusive) of p.

Thus, the cached points have dim = fromDim - toDim coordinates and there are \(n = \mathtt{toPoint}-\mathtt{fromPoint}\) of them. The original point set p itself is not modified.

Parameters

p	point set to be cached
fromPoint	number of skipped points (usually 0)
toPoint	1 + number of the last point selected from p
fromDim	number of skipped coordinates (often 0)
toDim	1 + index of last coordinate in the original points

Definition at line 78 of file CachedPointSet.java.

◆ CachedPointSet() [2/3]

umontreal.ssj.hups.CachedPointSet.CachedPointSet	(	PointSet	p,
		int	n,
		int	dim )

Same as CachedPointSet(p, 0, n, 0, dim).

Definition at line 112 of file CachedPointSet.java.

◆ CachedPointSet() [3/3]

umontreal.ssj.hups.CachedPointSet.CachedPointSet ( PointSet p )

Creates a new PointSet object that contains an array storing the points of p.

The number of points and their dimension are the same as in the original point set. Both must be finite.

Parameters

p	point set to be cached

Definition at line 123 of file CachedPointSet.java.

Member Function Documentation

◆ addRandomShift()

void umontreal.ssj.hups.CachedPointSet.addRandomShift	(	int	d1,
		int	d2,
		RandomStream	stream )

Generates a random shift, adds it to the contained point set, and re-caches the points.

See the doc of the overridden method addRandomShift(d1, d2, stream) in PointSet. In case there is no underlying point set, this method should be redefined to randomize the cached points.

Reimplemented from umontreal.ssj.hups.PointSet.

Reimplemented in umontreal.ssj.hups.IndependentPointsCached, umontreal.ssj.hups.LatinHypercube, umontreal.ssj.hups.SortedAndCutPointSet, umontreal.ssj.hups.StratifiedUnitCube, and umontreal.ssj.hups.StratifiedUnitCubeAnti.

Definition at line 153 of file CachedPointSet.java.

◆ fillCache()

void umontreal.ssj.hups.CachedPointSet.fillCache	(	int	fromDim,
		int	dim )

protected

Caches the points, skipping fromDim coordinates and taking the next dim ones.

Definition at line 100 of file CachedPointSet.java.

◆ getCoordinate()

double umontreal.ssj.hups.CachedPointSet.getCoordinate	(	int	i,
		int	j )

Returns \(u_{i,j}\), the coordinate \(j\) of the point \(i\).

When the points are randomized (e.g., a random shift is added), the values returned by this method should incorporate the randomizations. Richard: La méthode getCoordinate de certaines classes ne tient pas compte du random shift, contrairement à l’itérateur de la même classe. Faut-il que toutes les getCoordinate implémentent le random shift quand il existe? Oui.

Parameters

i	index of the point to look for
j	index of the coordinate to look for

Returns: the value of \(u_{i,j}\)

Reimplemented from umontreal.ssj.hups.PointSet.

Definition at line 216 of file CachedPointSet.java.

◆ getParentPointSet()

PointSet umontreal.ssj.hups.CachedPointSet.getParentPointSet ( )

Returns the reference point set that was passed to the constructor.

Definition at line 227 of file CachedPointSet.java.

◆ iterator()

PointSetIterator umontreal.ssj.hups.CachedPointSet.iterator ( )

Constructs and returns a point set iterator that gets the values directly from the cached array.

Reimplemented from umontreal.ssj.hups.PointSet.

Reimplemented in umontreal.ssj.hups.SortedAndCutPointSet.

Definition at line 131 of file CachedPointSet.java.

◆ randomize()

void umontreal.ssj.hups.CachedPointSet.randomize ( PointSetRandomization rand )

Randomizes the underlying point set using rand and re-caches the points.

In case there is no underlying point set, this method must be redefined to randomize the cached points in the appropriate way. If setRandomizeParent(false) was called, this method invokes rand.randomize(this) instead of on the parent point set.

Reimplemented from umontreal.ssj.hups.PointSet.

Reimplemented in umontreal.ssj.hups.IndependentPointsCached, umontreal.ssj.hups.LatinHypercube, umontreal.ssj.hups.SortedAndCutPointSet, umontreal.ssj.hups.StratifiedUnitCube, and umontreal.ssj.hups.StratifiedUnitCubeAnti.

Definition at line 165 of file CachedPointSet.java.

◆ setRandomizeParent()

void umontreal.ssj.hups.CachedPointSet.setRandomizeParent ( boolean randomizeParent )

If randomizeParent is true, calls to randomize() will be defered to the parent point set (this is the default); otherwise, the randomize method of the PointSetRandomization instance is invoked with this CachedPointSet instance as its argument.

Definition at line 141 of file CachedPointSet.java.

◆ sort()

public< T > void umontreal.ssj.hups.CachedPointSet.sort ( MultiDimSort< T > sort )

package

Sorts the cached points (only) with the given.

umontreal.ssj.util.MultiDimSort sorting algorithm sort. This does not affect the underlying point set p.

Definition at line 190 of file CachedPointSet.java.

◆ sortByCoordinate()

void umontreal.ssj.hups.CachedPointSet.sortByCoordinate ( int j )

Sorts the cached points by increasing order of coordinate j.

This is useful in the ArrayRQMC simulation method, for example. Note that the sort applies only to the cached points, and not to the original contained point set p.

Definition at line 180 of file CachedPointSet.java.

◆ stripCoordinates()

void umontreal.ssj.hups.CachedPointSet.stripCoordinates ( int d )

Removes the first d coordinates of each cached point.

This does not affect the underlying point set p. This could be useful in particular for the ArrayRQMC simulation method.

Definition at line 200 of file CachedPointSet.java.

◆ toString()

String umontreal.ssj.hups.CachedPointSet.toString ( )

Formats a string that contains information about the point set.

Returns: string representation of the point set information

Reimplemented from umontreal.ssj.hups.PointSet.

Reimplemented in umontreal.ssj.hups.IndependentPointsCached, umontreal.ssj.hups.LatinHypercube, umontreal.ssj.hups.SortedAndCutPointSet, umontreal.ssj.hups.StratifiedUnitCube, and umontreal.ssj.hups.StratifiedUnitCubeAnti.

Definition at line 207 of file CachedPointSet.java.

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

src/main/java/umontreal/ssj/hups/CachedPointSet.java

SSJ API Documentation Stochastic Simulation in Java

Classes

Public Member Functions

Protected Member Functions

Package Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ CachedPointSet() [1/3]

◆ CachedPointSet() [2/3]

◆ CachedPointSet() [3/3]

Member Function Documentation

◆ addRandomShift()

◆ fillCache()

◆ getCoordinate()

◆ getParentPointSet()

◆ iterator()

◆ randomize()

◆ setRandomizeParent()

◆ sort()

◆ sortByCoordinate()

◆ stripCoordinates()

◆ toString()