Difference between revisions of "Rn2"
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(nethack-366 -> nethack-367. Also fix an unversioned function reference.) |
(Fix the grammar from a previous copy edit.) |
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{{DISPLAYTITLE:rn2}} | {{DISPLAYTITLE:rn2}} | ||
{{randomvariable|name=rn2(x)|graph=rn2.svg|caption=[[wikipedia:Probability mass function|Probability mass function]] of rn2(10).|distribution=[[Wikipedia:discrete uniform distribution|uniform]]|mean=<math>(x-1)/2</math>|stddev=<math>\sqrt{(x^2-1)/12}</math>}} | {{randomvariable|name=rn2(x)|graph=rn2.svg|caption=[[wikipedia:Probability mass function|Probability mass function]] of rn2(10).|distribution=[[Wikipedia:discrete uniform distribution|uniform]]|mean=<math>(x-1)/2</math>|stddev=<math>\sqrt{(x^2-1)/12}</math>}} | ||
| − | '''rn2(x)''' is a pseudo-random number function used in the code of ''[[NetHack]]''.{{refsrc|nethack=3.6.7|src/rnd.c|99}} The function's purpose is to provide an "unweighted": the range of values is between 0 and x-1 inclusive (that is, 0 ≤ rn2(x) < x). | + | '''rn2(x)''' is a pseudo-random number function used in the code of ''[[NetHack]]''.{{refsrc|nethack=3.6.7|src/rnd.c|99}} The function's purpose is to provide an "unweighted" result: the range of values is between 0 and x-1 inclusive (that is, 0 ≤ rn2(x) < x). |
For example, to simulate a percentage chance: | For example, to simulate a percentage chance: | ||
Latest revision as of 01:46, 3 July 2024
| rn2(x) | |
|---|---|
 Probability mass function of rn2(10). | |
| Distribution | uniform |
| Mean | 
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| Standard deviation | 
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rn2(x) is a pseudo-random number function used in the code of NetHack.[1] The function's purpose is to provide an "unweighted" result: the range of values is between 0 and x-1 inclusive (that is, 0 ≤ rn2(x) < x).
For example, to simulate a percentage chance:
if (rn2(100) < chance) { ... }
Also,
!rn2(x)
is true with a 1/x probability.
See also rn1.
