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[SIC\]SIC RANDOM_SEED [DATETIME|URANDOM|Value]
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.