MersenneTwisterFast (Fiji Javadocs 0-SNAPSHOT API)

java.lang.Object
- pal.math.MersenneTwisterFast

All Implemented Interfaces:

Serializable
```
public class MersenneTwisterFast
extends Object
implements Serializable
```
MersenneTwisterFast: A simulation quality fast random number generator (MT19937) with the same public methods as java.util.Random.
About the Mersenne Twister. This is a Java version of the C-program for MT19937: Integer version. next(32) generates one pseudorandom unsigned integer (32bit) which is uniformly distributed among 0 to 2^32-1 for each call. next(int bits) >>>'s by (32-bits) to get a value ranging between 0 and 2^bits-1 long inclusive; hope that's correct. setSeed(seed) set initial values to the working area of 624 words. For setSeed(seed), seed is any 32-bit integer except for 0.
Reference. M. Matsumoto and T. Nishimura, "Mersenne Twister: A 623-Dimensionally Equidistributed Uniform Pseudo-Random Number Generator", ACM Transactions on Modeling and Computer Simulation, Vol. 8, No. 1, January 1998, pp 3--30.
Bug Fixes. This implementation implements the bug fixes made in Java 1.2's version of Random, which means it can be used with earlier versions of Java. See the JDK 1.2 java.util.Random documentation for further documentation on the random-number generation contracts made. Additionally, there's an undocumented bug in the JDK java.util.Random.nextBytes() method, which this code fixes.
Important Note. Just like java.util.Random, this generator accepts a long seed but doesn't use all of it. java.util.Random uses 48 bits. The Mersenne Twister instead uses 32 bits (int size). So it's best if your seed does not exceed the int range.
Sean Luke's web page
- added shuffling method (Alexei Drummond)

See Also:

Serialized Form

Constructor Summary

Constructors
Constructor and Description

MersenneTwisterFast()
Constructor using the time of day as default seed.

MersenneTwisterFast(long seed)
Constructor using a given seed.

Constructors
Constructor and Description
`MersenneTwisterFast()` Constructor using the time of day as default seed.
`MersenneTwisterFast(long seed)` Constructor using a given seed.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static boolean`	`getNextBoolean()` Access a default instance of this class, access is synchronized
`static byte`	`getNextByte()` Access a default instance of this class, access is synchronized
`static void`	`getNextBytes(byte[] bs)` Access a default instance of this class, access is synchronized
`static char`	`getNextChar()` Access a default instance of this class, access is synchronized
`static double`	`getNextDouble()` Access a default instance of this class, access is synchronized
`static float`	`getNextFloat()` Access a default instance of this class, access is synchronized
`static int`	`getNextInt()` Access a default instance of this class, access is synchronized
`static long`	`getNextLong()` Access a default instance of this class, access is synchronized
`static short`	`getNextShort()` Access a default instance of this class, access is synchronized
`boolean`	`nextBoolean()`
`byte`	`nextByte()`
`void`	`nextBytes(byte[] bytes)`
`char`	`nextChar()`
`double`	`nextDouble()`
`float`	`nextFloat()`
`double`	`nextGaussian()`
`int`	`nextInt()`
`int`	`nextInt(int n)` Returns an integer drawn uniformly from 0 to n-1.
`long`	`nextLong()`
`short`	`nextShort()`
`void`	`setSeed(long seed)` Initalize the pseudo random number generator.
`void`	`shuffle(int[] array)` Shuffles an array.
`void`	`shuffle(int[] array, int numberOfShuffles)` Shuffles an array.
`int[]`	`shuffled(int l)` Returns an array of shuffled indices of length l.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - MersenneTwisterFast
```
public MersenneTwisterFast()
```
    Constructor using the time of day as default seed.
  - MersenneTwisterFast
```
public MersenneTwisterFast(long seed)
```
    Constructor using a given seed. Though you pass this seed in as a long, it's best to make sure it's actually an integer.
    
    Parameters:
    
    seed - generator starting number, often the time of day.
- Method Detail
  - shuffle
```
public final void shuffle(int[] array)
```
    Shuffles an array.
  - shuffle
```
public final void shuffle(int[] array,
                          int numberOfShuffles)
```
    Shuffles an array. Shuffles numberOfShuffles times
  - shuffled
```
public int[] shuffled(int l)
```
    Returns an array of shuffled indices of length l.
    
    Parameters:
    
    l - length of the array required.
  - setSeed
```
public final void setSeed(long seed)
```
    Initalize the pseudo random number generator. The Mersenne Twister only uses an integer for its seed; It's best that you don't pass in a long that's bigger than an int.
    
    Parameters:
    
    seed - from constructor
  - nextInt
```
public final int nextInt()
```
  - nextShort
```
public final short nextShort()
```
  - nextChar
```
public final char nextChar()
```
  - nextBoolean
```
public final boolean nextBoolean()
```
  - nextByte
```
public final byte nextByte()
```
  - nextBytes
```
public final void nextBytes(byte[] bytes)
```
  - nextLong
```
public final long nextLong()
```
  - nextDouble
```
public final double nextDouble()
```
  - nextGaussian
```
public final double nextGaussian()
```
  - nextFloat
```
public final float nextFloat()
```
  - nextInt
```
public int nextInt(int n)
```
    Returns an integer drawn uniformly from 0 to n-1. Suffice it to say, n must be > 0, or an IllegalArgumentException is raised.
  - getNextByte
```
public static final byte getNextByte()
```
    Access a default instance of this class, access is synchronized
  - getNextBoolean
```
public static final boolean getNextBoolean()
```
    Access a default instance of this class, access is synchronized
  - getNextBytes
```
public static final void getNextBytes(byte[] bs)
```
    Access a default instance of this class, access is synchronized
  - getNextChar
```
public static final char getNextChar()
```
    Access a default instance of this class, access is synchronized
  - getNextDouble
```
public static final double getNextDouble()
```
    Access a default instance of this class, access is synchronized
  - getNextFloat
```
public static final float getNextFloat()
```
    Access a default instance of this class, access is synchronized
  - getNextLong
```
public static final long getNextLong()
```
    Access a default instance of this class, access is synchronized
  - getNextShort
```
public static final short getNextShort()
```
    Access a default instance of this class, access is synchronized
  - getNextInt
```
public static final int getNextInt()
```
    Access a default instance of this class, access is synchronized

Class MersenneTwisterFast

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

MersenneTwisterFast

MersenneTwisterFast

Method Detail

shuffle

shuffle

shuffled

setSeed

nextInt

nextShort

nextChar

nextBoolean

nextByte

nextBytes

nextLong

nextDouble

nextGaussian

nextFloat

nextInt

getNextByte

getNextBoolean

getNextBytes

getNextChar

getNextDouble

getNextFloat

getNextLong

getNextShort

getNextInt