Package cern.jet.random.engine
Class DRand
java.lang.Object
cern.colt.PersistentObject
cern.jet.random.engine.RandomEngine
cern.jet.random.engine.DRand
- All Implemented Interfaces:
DoubleFunction
,IntFunction
,Serializable
,Cloneable
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 double's in the open unit intervals (0.0f,1.0f) and (0.0,1.0), respectively.
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.
The seed can be any integer satisfying 0 < 4*seed+1 < 232. In other words, there must hold seed >= 0 invalid input: '&'invalid input: '&' seed < 1073741823.
Quality: This generator follows the multiplicative congruential method of the form
Performance: TO_DO
Implementation: TO_DO
Note that this implementation is not synchronized.
- Version:
- 1.0, 09/24/99
- See Also:
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Field Summary
FieldsFields inherited from class cern.colt.PersistentObject
serialVersionUID
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Constructor Summary
Constructors -
Method Summary
Methods inherited from class cern.jet.random.engine.RandomEngine
apply, apply, makeDefault, nextDouble, nextFloat, nextLong, raw
Methods inherited from class cern.colt.PersistentObject
clone
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Field Details
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current
private int current -
DEFAULT_SEED
public static final int DEFAULT_SEED- See Also:
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Constructor Details
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DRand
public DRand()Constructs and returns a random number generator with a default seed, which is a constant. -
DRand
public DRand(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.
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DRand
Constructs and returns a random number generator seeded with the given date.- Parameters:
d
- typically new java.util.Date()
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Method Details
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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 classRandomEngine
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setSeed
protected void setSeed(int seed) Sets the receiver's seed. This method resets the receiver's entire internal state. The following condition must hold: seed >= 0 invalid input: '&'invalid input: '&' seed < (232-1) / 4.- Parameters:
seed
- if the above condition does not hold, a modified seed that meets the condition is silently substituted.
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