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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 uni- form (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. Fish- man, `Multiplicative congruential random number generators with modulus 2**b: an exhaustive analysis for b = 32 and a par- tial 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.