CXML

LAPACK version 3.0

slaruv(3)

PURPOSE

SLARUV - return a vector of n random real numbers from a uniform (0,1)

SYNTAX

SUBROUTINE SLARUV( ISEED, N, X ) INTEGER N INTEGER ISEED( 4 ) REAL X( N )

DESCRIPTION

SLARUV returns a vector of n random real numbers from a uniform (0,1) distribution (n <= 128). This is an auxiliary routine called by SLARNV and CLARNV.

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) REAL 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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