ImageScience 3.0.0

imagescience.random
Class GammaGenerator

java.lang.Object
  extended by imagescience.random.GammaGenerator
All Implemented Interfaces:
RandomGenerator

public class GammaGenerator
extends java.lang.Object
implements RandomGenerator

Gamma random number generator of positive integer order. This implementation is based on the algorithm described by W. H. Press, S. A. Teukolsky, W. T. Vetterling, B. P. Flannery, Numerical Recipes in C: The Art of Scientific Computing (2nd edition), Cambridge University Press, Cambridge, 1992, Section 7.3, and uses UniformGenerator as a source of uniform random numbers.


Constructor Summary
GammaGenerator()
          Constructs a generator of random numbers from the first-order gamma distribution initialized with a random seed
GammaGenerator(int order)
          Constructs a generator of random numbers from the gamma distribution with given order and initialized with a random seed.
GammaGenerator(int order, int seed)
          Constructs a generator of random numbers from the gamma distribution with given order and initialized with the given seed.
 
Method Summary
 double next()
          Returns a random number from the gamma distribution with order specified at construction.
 double next(int order)
          Returns a random number from the gamma distribution with given order.
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

GammaGenerator

public GammaGenerator()
Constructs a generator of random numbers from the first-order gamma distribution initialized with a random seed


GammaGenerator

public GammaGenerator(int order)
Constructs a generator of random numbers from the gamma distribution with given order and initialized with a random seed.

Parameters:
order - The order of the gamma distribution. Must be larger than 0.
Throws:
java.lang.IllegalArgumentException - If order is less than or equal to 0.

GammaGenerator

public GammaGenerator(int order,
                      int seed)
Constructs a generator of random numbers from the gamma distribution with given order and initialized with the given seed.

Parameters:
order - The order of the gamma distribution. Must be larger than 0.
seed - The seed used for initialization of the generator.
Throws:
java.lang.IllegalArgumentException - If order is less than or equal to 0.
Method Detail

next

public double next()
Returns a random number from the gamma distribution with order specified at construction.

Specified by:
next in interface RandomGenerator
Returns:
A random number from the gamma distribution with order specified at construction.

next

public double next(int order)
Returns a random number from the gamma distribution with given order.

Returns:
A random number from the gamma distribution with given order.

ImageScience 3.0.0

Copyright (C) Erik Meijering. Permission to use this software and corresponding documentation for educational, research, and not-for-profit purposes, without a fee and without a signed licensing agreement, is granted, subject to the following terms and conditions.

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