SSJ
3.3.1
Stochastic Simulation in Java

Extends RandomStreamBase using a composite linear feedback shift register (LFSR) (or Tausworthe) RNG as defined in [147], [229] . More...
Public Member Functions  
LFSR113 ()  
Constructs a new stream.  
LFSR113 (String name)  
Constructs a new stream with the identifier name . More...  
void  setSeed (int[] seed) 
This method is discouraged for normal use. More...  
int []  getState () 
Returns the current state of the stream, represented as an array of four integers. More...  
LFSR113  clone () 
Clones the current generator and return its copy. More...  
void  resetStartStream () 
Reinitializes the stream to its initial state \(I_g\): \(C_g\) and \(B_g\) are set to \(I_g\).  
void  resetStartSubstream () 
Reinitializes the stream to the beginning of its current substream: \(C_g\) is set to \(B_g\).  
void  resetNextSubstream () 
Reinitializes the stream to the beginning of its next substream: \(N_g\) is computed, and \(C_g\) and \(B_g\) are set to \(N_g\).  
String  toString () 
Returns a string containing the current state of this stream. More...  
int  nextInt (int i, int j) 
Returns a (pseudo)random number from the discrete uniform distribution over the integers \(\{i,i+1,…,j\}\), using this stream. More...  
Public Member Functions inherited from RandomStreamBase  
abstract void  resetStartStream () 
Reinitializes the stream to its initial state \(I_g\): \(C_g\) and \(B_g\) are set to \(I_g\).  
abstract void  resetStartSubstream () 
Reinitializes the stream to the beginning of its current substream: \(C_g\) is set to \(B_g\).  
abstract void  resetNextSubstream () 
Reinitializes the stream to the beginning of its next substream: \(N_g\) is computed, and \(C_g\) and \(B_g\) are set to \(N_g\).  
abstract String  toString () 
Returns a string containing the current state of this stream. More...  
void  increasedPrecision (boolean incp) 
After calling this method with incp = true , each call to the RNG (direct or indirect) for this stream will return a uniform random number with more bits of precision than what is returned by nextValue , and will advance the state of the stream by 2 steps instead of 1 (i.e., nextValue will be called twice for each random number). More...  
double  nextDouble () 
Returns a uniform random number between 0 and 1 from the stream. More...  
void  nextArrayOfDouble (double[] u, int start, int n) 
Calls nextDouble n times to fill the array u . More...  
int  nextInt (int i, int j) 
Calls nextDouble once to create one integer between i and j . More...  
void  nextArrayOfInt (int i, int j, int[] u, int start, int n) 
Calls nextInt n times to fill the array u . More...  
String  formatState () 
Use the toString method.  
String  formatStateFull () 
Use the toStringFull method.  
RandomStreamBase  clone () 
Clones the current generator and return its copy. More...  
Static Public Member Functions  
static void  setPackageSeed (int[] seed) 
Sets the initial seed for the class LFSR113 to the four integers of the vector seed[0..3] . More...  
Protected Member Functions  
double  nextValue () 
Protected Member Functions inherited from RandomStreamBase  
abstract double  nextValue () 
This method should return the next random number (between 0 and 1) from the current stream. More...  
Additional Inherited Members  
Protected Attributes inherited from RandomStreamBase  
String  name = null 
boolean  prec53 = false 
boolean  anti = false 
Static Protected Attributes inherited from RandomStreamBase  
static double  invtwo24 = 5.9604644775390625e8 
Extends RandomStreamBase using a composite linear feedback shift register (LFSR) (or Tausworthe) RNG as defined in [147], [229] .
This generator is the LFSR113
proposed by [149] . It has four 32bit components combined by a bitwise xor. Its period length is \(\rho\approx2^{113}\). The values of \(V\), \(W\) and \(Z\) are \(2^{35}\), \(2^{55}\) and \(2^{90}\) respectively (see RandomStream for their definition). The seed of the RNG, and the state of a stream at any given step, are fourdimensional vectors of 32bit integers. The default initial seed of the RNG is ^{[1]} (987654321, 987654321, 987654321, 987654321). The nextValue
method returns numbers with 32 bits of precision.
LFSR113  (  String  name  ) 
Constructs a new stream with the identifier name
.
name  name of the stream 
LFSR113 clone  (  ) 
Clones the current generator and return its copy.
Implements CloneableRandomStream.
int [] getState  (  ) 
Returns the current state of the stream, represented as an array of four integers.
int nextInt  (  int  i, 
int  j  
) 
Returns a (pseudo)random number from the discrete uniform distribution over the integers \(\{i,i+1,…,j\}\), using this stream.
(Calls nextDouble
once.)
i  smallest integer that can be generated 
j  greatest integer that can be generated 
Implements RandomStream.

static 
Sets the initial seed for the class LFSR113
to the four integers of the vector seed[0..3]
.
This will be the initial state of the next created stream. The default seed for the first stream is ^{[2]} (987654321, 987654321, 987654321, 987654321). The first, second, third and fourth integers of seed
must be either negative, or greater than or equal to 2, 8, 16 and 128 respectively.
seed  array of 4 elements representing the seed 
void setSeed  (  int []  seed  ) 
This method is discouraged for normal use.
Initializes the stream at the beginning of a stream with the initial seed seed[0..3]
. The seed must satisfy the same conditions as in setPackageSeed
. This method only affects the specified stream; the others are not modified, so the beginning of the streams will not be spaced \(Z\) values apart. For this reason, this method should only be used in very exceptional cases; proper use of the reset...
methods and of the stream constructor is preferable.
seed  array of 4 elements representing the seed 
String toString  (  ) 
Returns a string containing the current state of this stream.
Implements RandomStream.