array_helpers.js

Array.range = function(start, count) {
	return Array.apply(null, { length: count })
		.map(function(v,i){
			return start + i;
		});
}

Array.prototype.clone = function() {
	return this.slice(0);
};

Array.prototype.square = function() {
	return this.map(function(n) {
		return Math.pow(n,2);
	});
}

Array.prototype.cube = function() {
	return this.map(function(n) {
		return Math.pow(n,3);
	});
}

Array.prototype.average = function() {
	return this.length > 0 ? this.sum() / this.length : NaN;
}

Array.prototype.sum = function() {
	return this.clone().reduce(function(a, b) {
		return a + b;
	});
}

Array.prototype.even = function() {
	return this.clone().filter(function(n) {
		return n % 2 == 0;
	});
}

Array.prototype.odd = function() {
	return this.clone().filter(function(n) {
		return n % 2 > 0;
	});
}