SSJ
V. labo.

umontreal.iro.lecuyer.discrepancy
Class SearcherKorobov

java.lang.Object
  extended by umontreal.iro.lecuyer.discrepancy.Searcher
      extended by umontreal.iro.lecuyer.discrepancy.SearcherKorobov

public class SearcherKorobov
extends Searcher

SearcherKorobov

This class implements searches to find the best Korobov lattices with respect to a given discrepancy. Given a positive integer n and a multiplier a, the points are defined by

ui = (i/n)(1, a, a2,…, as-1) mod 1

for i = 0,..., n - 1.

The discrepancy object in the constructor must fix the number of points n, the maximal dimension s of the lattice and possibly, the weight factors γj. Then the search program will examine different lattices with n, s and γj fixed in order to find the best amongst those examined.


Constructor Summary
SearcherKorobov(Discrepancy disc, boolean primeN)
          .
 
Method Summary
 double exhaust(int s)
          .
 double exhaustPrime(int s)
          .
 int getBestA()
          .
 double random(int s, int k)
          .
 double randomPrime(int s, int k)
          .
 
Methods inherited from class umontreal.iro.lecuyer.discrepancy.Searcher
getBestAs, getBestVal, initGen
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

SearcherKorobov

public SearcherKorobov(Discrepancy disc,
                       boolean primeN)
. \begin{tabb}The number of points $n$, the dimension $s$, and possibly the $s$
 we...
 ...or not (\texttt{false}).
 This is used in the \texttt{*Prime} methods.
 \end{tabb}

Method Detail

exhaust

public double exhaust(int s)
. \begin{tabb}
 Exhaustive search to find the best Korobov lattice (i.e. with the s...
 ...lattice. The method returns the best value found for the discrepancy.
 \end{tabb}

Overrides:
exhaust in class Searcher

exhaustPrime

public double exhaustPrime(int s)
. \begin{tabb}
 Similar to \method{exhaust}{int}\texttt{(s)}, except that only
 values of $a$\ \emph{relatively prime} to $n$\ are considered.
 \end{tabb}

Overrides:
exhaustPrime in class Searcher

random

public double random(int s,
                     int k)
. \begin{tabb}
 Random search to find the best Korobov lattice (with the smallest
 d...
 ...(n-1)$.
 The method returns the best value found for the discrepancy.
 \end{tabb}

Overrides:
random in class Searcher

randomPrime

public double randomPrime(int s,
                          int k)
. \begin{tabb}
 Similar to \method{random}{int,int}\texttt{(s, k)}, except that only
 values of $a$\ \emph{relatively prime} to $n$\ are considered.
 \end{tabb}

Overrides:
randomPrime in class Searcher

getBestA

public int getBestA()
. \begin{tabb}
 Returns the generator $a$\ of the lattice which gave the best value of the
 discrepancy in the last search.
 \end{tabb}


SSJ
V. labo.

To submit a bug or ask questions, send an e-mail to Pierre L'Ecuyer.