Uniform random number generators

random.js

// Citation: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/random

/*
 * Getting a random number from [0, max)
 */

// DO THIS (unbiased)
function getRandomInt(max) {
    var low = (-max >>> 0) % max;
    do { var n = Math.random() * 0x100000000 >>> 0; } while(n < low);
    return n % max;
}

// NOT THIS (biased)
function getRandomInt(max) {
    return Math.floor(Math.random() * max);
}

/*
 * Getting a random number from [min, max]
 */

// DO THIS (unbiased)
function getRandomIntInclusive(min, max) {
    var range = (max - min) + 1;
    var low = (-range >>> 0) % range;
    do { var n = Math.random() * 0x100000000 >>> 0; } while(n < low);
    return (n % range) + min;
}

// NOT THIS (biased)
function getRandomIntInclusive(min, max) {
    return Math.floor(Math.random() * (max - min + 1)) + min;
}