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43 lines
1.0 KiB
Plaintext
43 lines
1.0 KiB
Plaintext
NAME
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randbit - Blum-Blum-Shub pseudo-random number generator
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SYNOPSIS
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randombit([x])
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TYPES
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x integer
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return integer
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DESCRIPTION
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If x > 0, randombit(x) returns a pseudo-random integer in [0, 2^x),
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i.e. the same as rand(2^x). If the integer returned is
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b_1 * 2^(x-1) + b_2 * 2^(x-2) + ... + b_n,
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where each b_i is 0 or 1, then b_1, b_2, ..., b_n may be
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considered as a sequence of x random bits.
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If x <= 0, randombit(x) causes the random-number generator to skip
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abs(x) bits, and returns abs(x).
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If x is omitted, it is assumed to have the value of 1.
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See the random() help page for details on the additive 55 shuffle
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pseudo-random number generator.
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EXAMPLE
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> print srandom(0), randombit(20), randombit(20), randombit(20)
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RANDOM state 523139 567456 693508
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> print srandom(0), randombit(-20), randombit(20), randombit(-20)
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RANDOM state 20 567456 20
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LIMITS
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x != 0
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LIBRARY
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void zrandom(long cnt, ZVALUE *res)
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SEE ALSO
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srand, randbit, isrand, rand, srandom, israndom
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