determinebasestats.js

/**
 * This program calculates the average number of pokemon you would need to
 * catch to determine the base stats of a species at level 50.
 *
 *     Answer: 48.655998 ± 19.320596468782078
 *
 * @author Cathy J. Fitzpatrick <cathy@cathyjf.com>
 * @licence public domain
 */

var runTrial = function() {
	var seenMin = [false, false, false, false, false, false];
	var seenMax = [false, false, false, false, false, false];
	var trials = 0;
	do {
		++trials;
		for (var i = 0; i < 6; ++i) {
			var v = Math.floor(Math.random() * 16);
			if (v === 0) {
				seenMin[i] = true;
			} else if (v === 1) {
				seenMax[i] = true;
			}
		}
	} while ((seenMin.indexOf(false) !== -1) || (seenMax.indexOf(false) !== -1));
	return trials;
};

const TRIALS = 1000000;
var values = [];
var sum = 0;
for (var i = 0; i < TRIALS; ++i) {
	var v = runTrial();
	values.push(v);
	sum += v;
}
var mean = sum / TRIALS;
var stdsum = 0;
for (var i = 0; i < values.length; ++i) {
	var v = values[i] - mean;
	stdsum += v * v;
}
var stddev = Math.sqrt(stdsum / (values.length - 1));
console.log('Answer: ' + mean + ' ± ' + stddev);