org.das2.math
Class PoissonDistribution

java.lang.Object
  org.das2.math.PoissonDistribution

public class PoissonDistribution
extends java.lang.Object

Constructor Summary

PoissonDistribution()

Method Summary

static int

poisson(double L, java.util.Random random) This function generates a random variate with the poisson distribution.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

PoissonDistribution

public PoissonDistribution()

Method Detail

poisson

public static int poisson(double L,
                          java.util.Random random)

This function generates a random variate with the poisson distribution. Uses inversion by chop-down method for L < 17, and ratio-of-uniforms method for L >= 17. For L < 1.E-6 numerical inaccuracy is avoided by direct calculation. For L > 2E9 too big--throws IllegalArgumentException