Find the median of an array of numbers using JavaScript

median.js

function median(arr) {
	let middle = Math.floor((arr.length-1)/2);

	if (arr.length % 2) {
		return arr[middle]; // odd
	} else {		
		return (arr[middle]+arr[middle+1])/2; // even
	}

}

// test
const odd = [1,2,3,4,5];
const even = [1,2,3,4,5,6];
console.log(median(even));

// some neat helper functions

// sum the array - neat when looking for the average
function sumArr(arr) {
	return arr.reduce((a, b) => a + b, 0);
}

// sort the array - neat before applying median()
function sortArr(arr) {
	return arr.sort((a, b) => a - b);
}