[erlang-questions] Random behaviour
Tue Sep 7 16:35:14 CEST 2010
In the message <OF90470578.66305B76-ONC1257797.004AE2A8-C1257797.004C6E70@REDACTED>
dated Tue, Sep 07, 2010 at 03:54:26PM +0200,
Olivier BOUDEVILLE <olivier.boudeville@REDACTED> writes:
> Shouldn't the link read "http://github.com/jj1bdx/sfmt-erlang" ?
You are right. My mistake.
> By the way, regarding that seeding: how could it be performed reliably
> without the crypto module? I believe that crypto needs libssl which may
> not be available on some platforms. Any idea?
/dev/random either on Linux or on FreeBSD will work as (at least
practically) a reliable seeder, though I suggest crypto:rand_bytes/1
> On a side note, maybe a neat addition around sfmt would be to provide a
> function which performs an efficient uniform shuffle of a user-specified
> list (linked to the "Speedy unsort" discussion,
> Unless it would be too far stretched from the purpose of such a library?
I remember the discussion, though I don't really recall the shuffling
algorithm itself now. SFMT is basically a 32bit integer PRNG so you can
use it for whatever you want. sfmt:gen_rand32_max/1 will be helpful
(generating the integer sequence between 0 to N-1)
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