seed-random ( rnd seed -- rnd )
Generating random integers » Random protocol

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random-bytes* ( n rnd -- byte-array )

Vocabulary
random

Inputs

rnd	a random number generator
seed	a seed specific to the random number generator

Outputs

rnd	a random number generator

Word description
Seed the random number generator. Repeatedly seeding the random number generator should provide the same sequence of random numbers.

Notes
Not supported on all random number generators.

Definition

IN: random

GENERIC#: seed-random 1 ( rnd seed -- rnd )

Methods

USING: accessors kernel math random random.cmwc sequences ;

M: cmwc seed-random
    [ Q>> >>Q ] [ Q>> length 1 - >>i ] [ c>> >>c ] tri ;


USING: accessors kernel math random random.lagged-fibonacci
random.lagged-fibonacci.private sequences ;

M:: lagged-fibonacci seed-random
    ( lagged-fibonacci seed -- rnd )
    seed normalize-seed seed! seed 30082 /i
    :> ij seed 30082 ij * - :> kl ij 177 /i 177 mod 2 +
    :> i! ij 177 mod 2 + :> j! kl 169 /i 178 mod 1 +
    :> k! kl 169 mod :> l! lagged-fibonacci u>> [
        drop
        0.0 :> s! 0.5 :> t! 0.0 :> m! lagged-fibonacci-sig-bits 
        [
            i j * 179 mod k * 179 mod m! j i! k j! m k! 53 l *
            1 + 169 mod l! l m * 64 mod 31 > [ s t + s! ] when
            t 0.5 * t!
        ] times s
    ] map! drop lagged-fibonacci p-r >>pt0 q-r >>pt1 ; inline


USING: accessors kernel random random.mersenne-twister.private ;

M: mersenne-twister seed-random
    init-mt-seq >>seq dup mt-generate ;


USING: accessors random random.dummy ;

M: random-dummy seed-random >>i ;


USING: accessors kernel random random.sfmt.private ;

M: sfmt seed-random
    [ [ state>> ] dip >>seed drop ] [ drop init-sfmt ] 2bi ;