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REAL FUNCTION sla_RANDOM (SEED)
*+
* - - - - - - -
* R A N D O M
* - - - - - - -
*
* Generate pseudo-random real number in the range 0 <= X < 1.
* (single precision)
*
* !!! Sun 4 dependent !!!
*
* Given:
* SEED real an arbitrary real number
*
* Notes:
*
* 1) The result is a pseudo-random REAL number in the range
* 0 <= sla_RANDOM < 1.
*
* 2) SEED is used first time through only.
*
* Called: RAND (a REAL function from the Sun Fortran Library)
*
* P.T.Wallace Starlink 14 October 1991
*
* Copyright (C) 1995 Rutherford Appleton Laboratory
*-
IMPLICIT NONE
REAL SEED
REAL RAND
REAL AS
INTEGER ISEED
LOGICAL FIRST
SAVE FIRST
DATA FIRST /.TRUE./
* If first time, turn SEED into a large, odd integer, and start the
* generator
IF (FIRST) THEN
AS=ABS(SEED)+1.0
ISEED=NINT(AS/10.0**(NINT(ALOG10(AS))-6))
IF (MOD(ISEED,2).EQ.0) ISEED=ISEED+1
FIRST=.FALSE.
AS=RAND(ISEED)
END IF
* Next pseudo-random number
sla_RANDOM=RAND(0)
END
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