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authorDimitri Sokolyuk <demon@dim13.org>2018-09-21 22:00:43 +0200
committerDimitri Sokolyuk <demon@dim13.org>2018-09-21 22:00:43 +0200
commitd00a92eb232b03cc5e19a33c407c0f0efd50b784 (patch)
tree6fc72e166e4912a054dc6ae2799c7e4795804c16 /forth/rand.fs
parent2f83a0bea9da444e3d70569eba3d6847ca02be03 (diff)
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+\ Fast Random Number Generator algorithm by George Marsaglia "Xorshift RNGs"
+
+-rnd
+marker -rnd
+
+: xorshift ( n -- n )
+ dup #13 lshift xor
+ dup #17 rshift xor
+ dup #5 lshift xor
+;
+
+variable (rnd) \ seed
+ticks (rnd) ! \ initialize seed
+
+: rnd ( -- n )
+ (rnd) @ xorshift dup (rnd) !
+;