com.softsynth.jmsl
Class JMSLRandom

java.lang.Object
  com.softsynth.jmsl.JMSLRandom

public class JMSLRandom
extends java.lang.Object

Random number class. Algorithm from Cooper/Clancy "Oh! Pascal!"

Author:

Phil Burk and Nick Didkovsky

Field Summary

static int

NUM_GAUSS_LOOPS The higher the number of loops, the better gauss() approximates bell curve (Central Limit Theorem Method).

Constructor Summary

JMSLRandom()

Method Summary

static double	choose()
static double	choose(double high)
static double	choose(double low, double high)
static int	choose(int high)
static int	choose(int low, int high)
static double	choosePlusMinus(double range) return random double between +range and -range
static int	choosePlusMinus(int range) return random integer between +range and -range, inclusive
static double	gauss(double sigma, double xmu) Return a Gaussian distributed value using Central Limit Theorem Method.
static int	getSeed()
static void	main(java.lang.String[] args)
static int	nextSeed()
static int	qa()
static void	randomize() set random seed from time.
static void	setSeed(int s)

Methods inherited from class java.lang.Object

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

Field Detail

NUM_GAUSS_LOOPS

public static int NUM_GAUSS_LOOPS

The higher the number of loops, the better gauss() approximates bell curve (Central Limit Theorem Method). Defaults to 20, see http://www.dspguru.com/howto/tech/wgn2.htm

Constructor Detail

JMSLRandom

public JMSLRandom()

Method Detail

randomize

public static void randomize()

set random seed from time. Call getSeed() to store the random seed generated here

setSeed

public static void setSeed(int s)

getSeed

public static int getSeed()

Returns:

current seed

nextSeed

public static int nextSeed()

choose

public static double choose()

Returns:

random float [0..1)

choose

public static int choose(int high)

Returns:

random int [0..high)

choose

public static double choose(double high)

Returns:

random double [0..high)

choose

public static int choose(int low,
                         int high)

Returns:

random int [low..high)

choose

public static double choose(double low,
                            double high)

Returns:

random double [low..high)

choosePlusMinus

public static int choosePlusMinus(int range)

return random integer between +range and -range, inclusive

choosePlusMinus

public static double choosePlusMinus(double range)

return random double between +range and -range

gauss

public static double gauss(double sigma,
                           double xmu)

Return a Gaussian distributed value using Central Limit Theorem Method. sigma (standard deviation) controls narrowness of bell, xmu (mean) controls the centering of bell. Small sigmas make narrow bells. Comments from Matt Donadio at http://www.dspguru.com/howto/tech/wgn2.htm, "The drawback to this method is that X will be in the range [-N, N], instead of (-Infinity, Infinity) and if the calls to uniform are not truly independent, then the noise will no longer be white. Jeruchim, et. al., recommend N >=20 for good results."

qa

public static int qa()

main

public static void main(java.lang.String[] args)