Unbias a random generator: Difference between revisions
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5: 20.05% 50.00%
6: 17.00% 49.88%</pre>
=={{header|jq}}==
'''Adapted from [[#Wren]]'''
{{works with|jq}}
'''Also works with gojq, the Go implementation of jq'''
In this entry, /dev/random is used as a source of entropy,
and so a suitable invocation would be:
<pre>
< /dev/random tr -cd '0-9' | fold -w 1 | jq -Mcnr -f unbias.jq
</pre>
'''unbias.jq'''
<syntaxhighlight lang=jq>
### Utility Functions
# Output: a PRN in range(0;$n) where $n is .
def prn:
if . == 1 then 0
else . as $n
| (($n-1)|tostring|length) as $w
| [limit($w; inputs)] | join("") | tonumber
| if . < $n then . else ($n | prn) end
| debug
end;
def round: ((. * 100) | floor) / 100;
# input: n
# output: boolean, such that P(true) == 1/n
def biased:
prn == 1 | debug;
def unbiased:
. as $n
| {}
| until( .a != .b; {a: ($n|biased), b: ($n|biased)})
| .a;
def task($m):
def f(x;y;z): "\(x): \(y|round)% \(z|round)%";
range(3;7) as $n
| reduce range(0; $m) as $i ( {c1:0, c2:0};
if ($n|biased) then .c1 += 1 else . end
| if ($n|unbiased) then .c2 += 1 else . end)
| f($n; 100 * .c1 / $m; 100 * .c2 / $m);
task(50000)
</syntaxhighlight>
{{output}}
<pre>
3: 33.61% 50.09%
4: 25.48% 50.21%
5: 20.32% 50.47%
6: 16.35% 49.72%
</pre>
=={{header|Julia}}==
| |||