Random numbers: Difference between revisions

=={{header|Wren}}==

<lang ecmascript>import "random" for Random

var rand = Random.new()

var randNormal = Fn.new { (-2 * rand.float().log).sqrt * (2 * Num.pi * rand.float()).cos }

var stdDev = Fn.new { |a, m|

var c = a.count

return ((a.reduce(0) { |acc, x| acc + x*x } - m*m*c) / c).sqrt

}

var n = 1000

var numbers = List.filled(n, 0)

var mu = 1

var sigma = 0.5

var sum = 0

for (i in 0...n) {

numbers[i] = mu + sigma*randNormal.call()

sum = sum + numbers[i]

}

var mean = sum / n

System.print("Actual mean : %(mean)")

System.print("Actual std dev: %(stdDev.call(numbers, mean))")</lang>

{{out}}

Sample run:

<pre>

Actual mean : 1.0053988699746

Actual std dev: 0.4961645117026

</pre>