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    This command resets the Fortran random seed used to initialize  the  se-
    quence  of  pseudorandom  numbers  returned  by the functions RANDOM and
    NOISE. Several arguments are allowed:
      - DATETIME: compute a seed based on current date  and  time.  This  is
        portable but not highly random, e.g. 2 processes running at the same
        time can end with the same seed.
      - URANDOM: use the operating system special  file  /dev/urandom  as  a
        random  number  generator, if available. This is the best choice but
        it is not fully portable.
      - Value: the user can specify its own seed  (integer  value).  Reusing
        the same value will ensure the same sequence of pseudorandom numbers
        later on, which can be useful depending on the context.
    Note that this command affects the seed, i.e. the starting point of  the
    sequence  of pseudo-random numbers. It does not affect the randomness of
    those numbers (i.e. you can safely use the Value 1 if you want).

    The default at startup is DATETIME, i.e. the  sequence  will  always  be
    different  from one session to another. This default can be overriden by
    setting the Sic logical GILDAS_RANDOM_SEED to DATETIME, URANDOM,  or  an
    integer value in the file $HOME/.gag.dico

    Without  argument,  the command displays the current Fortran random seed
    in use. For debugging purpose.

Gildas manager 2014-07-01