SSJ  3.2.1
Stochastic Simulation in Java
Public Member Functions | Protected Attributes | List of all members
KorobovLattice Class Reference

This class implements Korobov lattices, which represents the same point sets as in class LCGPointSet, but implemented differently. More...

Inheritance diagram for KorobovLattice:
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Collaboration diagram for KorobovLattice:
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Public Member Functions

 KorobovLattice (int n, int a, int s)
 Instantiates a Korobov lattice point set with modulus \(n\) and multiplier \(a\) in dimension \(s\).
 
 KorobovLattice (int n, int a, int s, int t)
 Instantiates a shifted Korobov lattice point set with modulus \(n\) and multiplier \(a\) in dimension \(s\). More...
 
void setNumPoints (int n)
 Resets the number of points of the lattice to \(n\). More...
 
int getA ()
 Returns the multiplier \(a\) of the lattice. More...
 
String toString ()
 
- Public Member Functions inherited from Rank1Lattice
 Rank1Lattice (int n, int[] a, int s)
 Instantiates a Rank1Lattice with \(n\) points and lattice vector \(a\) of dimension \(s\). More...
 
void setNumPoints (int n)
 Resets the number of points of the lattice to \(n\). More...
 
int [] getAs ()
 Returns the generator \(a_j\) of the lattice. More...
 
void addRandomShift (int d1, int d2, RandomStream stream)
 Adds a random shift to all the points of the point set, using stream stream to generate the random numbers. More...
 
void clearRandomShift ()
 Clears the random shift.
 
String toString ()
 
double getCoordinate (int i, int j)
 
PointSetIterator iterator ()
 
- Public Member Functions inherited from PointSet
int getDimension ()
 Returns the dimension (number of available coordinates) of the point set. More...
 
int getNumPoints ()
 Returns the number of points. More...
 
abstract double getCoordinate (int i, int j)
 Returns \(u_{i,j}\), the coordinate \(j\) of the point \(i\). More...
 
PointSetIterator iterator ()
 Constructs and returns a point set iterator. More...
 
void setStream (RandomStream stream)
 Sets the random stream used to generate random shifts to stream. More...
 
RandomStream getStream ()
 Returns the random stream used to generate random shifts. More...
 
void randomize (PointSetRandomization rand)
 Randomizes the point set using the given rand. More...
 
void addRandomShift (int d1, int d2, RandomStream stream)
 This method does nothing for this generic class. More...
 
void addRandomShift (RandomStream stream)
 This method does nothing for this generic class. More...
 
void addRandomShift (int d1, int d2)
 Similar to addRandomShift(d1, d2, stream), with the current random stream.
 
void addRandomShift ()
 Similar to addRandomShift(0, d2, stream) with the current random stream and d2 the dimension of the current random shift.
 
void clearRandomShift ()
 Erases the current random shift, if any.
 
void randomize (int fromDim, int toDim, RandomStream stream)
 By default, this method simply calls addRandomShift (fromDim, toDim, stream), which does nothing.
 
void randomize (RandomStream stream)
 By default, this method simply calls randomize(0, dim, stream).
 
void randomize (int d1, int d2)
 By default, this method simply calls addRandomShift(d1, d2).
 
void randomize ()
 By default, this method simply calls addRandomShift().
 
void unrandomize ()
 By default, this method simply calls clearRandomShift().
 
String toString ()
 Formats a string that contains information about the point set. More...
 
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. More...
 
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 \(n\) points. More...
 
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. More...
 
String formatPoints (PointSetIterator iter, int n, int d)
 Same as invoking formatPoints(n, d), but prints the points by calling iter repeatedly. More...
 
String formatPointsBase (int b)
 Similar to formatPoints(), but the points coordinates are printed in base \(b\). More...
 
String formatPointsBase (int n, int d, int b)
 Similar to formatPoints(n, d), but the points coordinates are printed in base \(b\). More...
 
String formatPointsBase (PointSetIterator iter, int b)
 Similar to formatPoints(iter), but the points coordinates are printed in base \(b\). More...
 
String formatPointsBase (PointSetIterator iter, int n, int d, int b)
 Similar to formatPoints(iter, n, d), but the points coordinates are printed in base \(b\). More...
 
String formatPointsNumbered ()
 Same as invoking formatPointsNumbered(n, d) with \(n\) and \(d\) equal to the number of points and the dimension, respectively. More...
 
String formatPointsNumbered (int n, int d)
 Same as invoking formatPoints(n,d), except that the points are numbered. More...
 

Protected Attributes

int genA
 
- Protected Attributes inherited from Rank1Lattice
int [] genAs
 
double [] v
 
double normFactor
 
double [] shift
 
- Protected Attributes inherited from PointSet
double EpsilonHalf = 1.0 / Num.TWOEXP[55]
 
int dim = 0
 
int numPoints = 0
 
int dimShift = 0
 
int capacityShift = 0
 
RandomStream shiftStream
 

Additional Inherited Members

- Protected Member Functions inherited from Rank1Lattice
long modPower (long a, int e, int m)
 
double radicalInverse (int base, int i)
 
- Static Protected Attributes inherited from PointSet
static final int MAXBITS = 31
 

Detailed Description

This class implements Korobov lattices, which represents the same point sets as in class LCGPointSet, but implemented differently.

The parameters are the modulus \(n\) and the multiplier \(a\), for an arbitrary integer \(1 \le a < n\). [When \(a\) is outside the interval \([1,n)\), then we replace \(a\) by ( \(a \bmod n\)) in all calculations.] The number of points is \(n\), their dimension is \(s\), and they are defined by

\[ \mathbf{u}_i = (i/n)(1, a, a^2, …, a^{s-1}) \bmod1 \]

for \(i=0,…,n-1\).

It is also possible to build a "shifted" Korobov lattice with the first \(t\) coordinates rejected. The \(s\)-dimensionnal points are then defined as

\[ \mathbf{u}_i = (i/n)(a^t, a^{t+1}, a^{t+2}, …, a^{t+s-1}) \bmod1 \]

for \(i=0,…,n-1\) and fixed \(t\).

Constructor & Destructor Documentation

◆ KorobovLattice()

KorobovLattice ( int  n,
int  a,
int  s,
int  t 
)

Instantiates a shifted Korobov lattice point set with modulus \(n\) and multiplier \(a\) in dimension \(s\).

The first \(t\) coordinates of a standard Korobov lattice are dropped as described above. The case \(t=0\) corresponds to the standard Korobov lattice.

Member Function Documentation

◆ getA()

int getA ( )

Returns the multiplier \(a\) of the lattice.

(The original one before it is reset to \(a \bmod n\)).

◆ setNumPoints()

void setNumPoints ( int  n)

Resets the number of points of the lattice to \(n\).

The values of \(s\), \(a\) and \(t\) are unchanged.


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