Age | Commit message (Collapse) | Author |
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According to the documentation, rand:export_seed/0 should return
'undefined' if the seed has not been intialized. However, it will
create and return a seed. That means that the following code
will not work as expected:
case rand:export_seed() of
undefined -> rand:seen({1,2,3});
_ -> ok
end,
rand:uniform(Range)
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It is needed in various tests. It uses the Ziggurat algorithm, which
is the fastest that I know.
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The old random module contains an old algorithm which have flaws
and the api requires the user to invoke seed and or checking if seed have
been invoked, if a non constant seed is to be used.
The api contains the following features:
- The user can invoke rand:unform/[0|1] directly and get a non constant seeding.
- The api is split in functional and non functional functions,
i.e. usage of _s functions will not affect the process dictionary.
- The api contains several algorithms with different characteristics and
can be extended with new algorithms in the future.
- Contains state of the art random number generators.
- Default algorithm is taylor made for erlang to be fast on 64bits machines.
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