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DRANDGENERALDISCRETE / SRANDGENERALDISCRETE

Takes a reference vector initialized via one of DRANDBINOMIALREFERENCE, DRANDGEOMETRICREFERENCE, DRANDHYPERGEOMETRICREFERENCE, DRANDNEGATIVEBINOMIALREFERENCE, DRANDPOISSONREFERENCE and generates a vector of random variates from it.

(Note that SRANDGENERALDISCRETE is the single precision version of DRANDGENERALDISCRETE. The argument lists of both routines are identical except that any double precision arguments of DRANDGENERALDISCRETE are replaced in SRANDGENERALDISCRETE by single precision arguments - type REAL in FORTRAN or type float in C).

— SUBROUTINE: DRANDGENERALDISCRETE (N,REF,STATE,X,INFO)
— Input: INTEGER N

On input: number of variates required.
Constraint: N>=0.

— Input: DOUBLE PRECISION REF(*)

On input: reference vector generated by one of the following: DRANDBINOMIALREFERENCE, DRANDGEOMETRICREFERENCE, DRANDHYPERGEOMETRICREFERENCE, DRANDNEGATIVEBINOMIALREFERENCE, DRANDPOISSONREFERENCE.

— Input/Output: INTEGER STATE(*)

The STATE vector holds information on the state of the base generator being used and as such its minimum length varies. Prior to calling DRANDGENERALDISCRETE STATE must have been initialized. See Initialization of the Base Generators for information on initialization of the STATE variable.
On input: the current state of the base generator.
On output: the updated state of the base generator.

— Output: INTEGER X(N)

On output: vector of variates from the specified distribution.

— Output: INTEGER INFO

On output: INFO is an error indicator. On successful exit, INFO contains 0. If INFO = -i on exit, the i-th argument had an illegal value. 

     Example:
     

     
          C      Generate 100 values from the Binomial distribution
                 INTEGER LSTATE,N
                 PARAMETER (LSTATE=16,N=100)
                 INTEGER I,INFO,SEED(1),STATE(LSTATE)
                 INTEGER M
                 DOUBLE PRECISION P
                 INTEGER X(N)
                 INTEGER LREF
                 DOUBLE PRECISION REF(1000)
          
          C      Set the seed
                 SEED(1) = 1234
          
          C      Read in the distributional parameters
                 READ(5,*) M,P
          
          C      Initialize the STATE vector
                 CALL DRANDINITIALIZE(1,1,SEED,1,STATE,LSTATE,INFO)
          
          C      Initialize the reference vector
                 LREF = 1000
                 CALL DRANDBINOMIALREFERENCE(M,P,REF,LREF,INFO)
          
          C      Generate N variates from the Binomial distribution
                 CALL DRANDGENERALDISCRETE(N,REF,STATE,X,INFO)
          C      Print the results
                 WRITE(6,*) (X(I),I=1,N)