DLARUV(3F)DLARUV(3F)NAME
DLARUV - return a vector of n random real numbers from a uniform (0,1)
SYNOPSIS
SUBROUTINE DLARUV( ISEED, N, X )
INTEGER N
INTEGER ISEED( 4 )
DOUBLE PRECISION X( N )
PURPOSE
DLARUV returns a vector of n random real numbers from a uniform (0,1)
distribution (n <= 128).
This is an auxiliary routine called by DLARNV and ZLARNV.
ARGUMENTS
ISEED (input/output) INTEGER array, dimension (4)
On entry, the seed of the random number generator; the array
elements must be between 0 and 4095, and ISEED(4) must be odd.
On exit, the seed is updated.
N (input) INTEGER
The number of random numbers to be generated. N <= 128.
X (output) DOUBLE PRECISION array, dimension (N)
The generated random numbers.
FURTHER DETAILS
This routine uses a multiplicative congruential method with modulus 2**48
and multiplier 33952834046453 (see G.S.Fishman,
2**b: an exhaustive analysis for b = 32 and a partial analysis for b =
48', Math. Comp. 189, pp 331-344, 1990).
48-bit integers are stored in 4 integer array elements with 12 bits per
element. Hence the routine is portable across machines with integers of
32 bits or more.
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