cern.jet.random.tfloat.engine
Class FRand

java.lang.Object
  cern.colt.PersistentObject
      cern.jet.random.tfloat.engine.FloatRandomEngine
          cern.jet.random.tfloat.engine.FRand

All Implemented Interfaces:

FloatFunction, IntFunction, Serializable, Cloneable

public class FRand
extends FloatRandomEngine

Quick medium quality uniform pseudo-random number generator. Produces uniformly distributed int's and long's in the closed intervals [Integer.MIN_VALUE,Integer.MAX_VALUE] and [Long.MIN_VALUE,Long.MAX_VALUE], respectively, as well as float's and float's in the open unit intervals (0.0f,1.0f) and (0.0,1.0), respectively.

The seed can be any integer satisfying 0 < 4*seed+1 < 2³². In other words, there must hold seed >= 0 && seed < 1073741823.

Quality: This generator follows the multiplicative congruential method of the form

z(i+1) = a * z(i) (mod m) with a=663608941 (=0X278DDE6DL), m=2³².

z(i) assumes all different values 0 < 4*seed+1 < m during a full period of 2³⁰.

Performance: TO_DO

Implementation: TO_DO

Note that this implementation is not synchronized.

Version:

1.0, 09/24/99

Author:

wolfgang.hoschek@cern.ch

See Also:

FloatMersenneTwister, Random, Serialized Form

Field Summary

static int

DEFAULT_SEED

Constructor Summary

FRand()
Constructs and returns a random number generator with a default seed, which is a constant.

FRand(Date d)
Constructs and returns a random number generator seeded with the given date.

FRand(int seed)
Constructs and returns a random number generator with the given seed.

Method Summary

int	nextInt() Returns a 32 bit uniformly distributed random number in the closed interval [Integer.MIN_VALUE,Integer.MAX_VALUE] (including Integer.MIN_VALUE and Integer.MAX_VALUE).

Methods inherited from class cern.jet.random.tfloat.engine.FloatRandomEngine

apply, apply, makeDefault, nextFloat, nextLong, raw

Methods inherited from class cern.colt.PersistentObject

clone

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_SEED

public static final int DEFAULT_SEED

See Also:

Constant Field Values

Constructor Detail

FRand

public FRand()

Constructs and returns a random number generator with a default seed, which is a constant.

FRand

public FRand(int seed)

Constructs and returns a random number generator with the given seed.

Parameters:

seed - should not be 0, in such a case DRand.DEFAULT_SEED is substituted.

FRand

public FRand(Date d)

Constructs and returns a random number generator seeded with the given date.

Parameters:

d - typically new java.util.Date()

Method Detail

nextInt

public int nextInt()

Returns a 32 bit uniformly distributed random number in the closed interval [Integer.MIN_VALUE,Integer.MAX_VALUE] (including Integer.MIN_VALUE and Integer.MAX_VALUE).

Specified by:

nextInt in class FloatRandomEngine