DragonFly On-Line Manual Pages

Search: Section:  

SNOBOL4RANDOM(1)       DragonFly General Commands Manual      SNOBOL4RANDOM(1)


NAME

       snobol4random - SNOBOL4 random number functions


SYNOPSIS

       -INCLUDE 'random.sno'

       NUMBER = RANDOM()

       SRANDOM(NUMBER)

       SRANDOMDEV()


DESCRIPTION

       The RANDOM() function uses a non-linear additive feedback random number
       generator employing a default table of size 31 long integers to return
       successive pseudo-random numbers in the range from 0 to (2**31)-1.  The
       period of this random number generator is very large, approximately
       16*((2**31)-1).

       The SRANDOM() function sets its INTEGER argument seed as the seed for a
       new sequence of pseudo-random numbers to be returned by RANDOM().
       These sequences are repeatable by calling SRANDOM() with the same seed
       value.  RANDOM() will by default produce a sequence of numbers that can
       be duplicated by calling SRANDOM() with 1 as the seed.

       The SRANDOMDEV() routine initializes a state array using the random(4)
       random number device (if available) which returns good random numbers,
       suitable for cryptographic use.  Note that this particular seeding
       procedure can generate states which are impossible to reproduce by
       calling SRANDOM() with any value, since the succeeding terms in the
       state buffer are no longer derived from the LC algorithm applied to a
       fixed seed.  Data from the random(4) device may be precious, and
       repeated calls to SRANDOMDEV() should be avoided.  When the random(4)
       device is not available, a 32-bit seed will be generated using time,
       process id, and an element of the process stack.


SEE ALSO

       snobol4(1), random(3), random(4)


AUTHOR

       Philip L. Budne

SNOBOL                            4 Jan 2012                  SNOBOL4RANDOM(1)

Search: Section: