Desvio médio absoluto em JS

dam.js

//Desvio medio absoluto
function dam(input){
	let sum = input.reduce((acc,val) => acc+val);
	let mean = sum/input.length;
	let desvAbs = input.map(val => Math.abs(val - mean));
	let sumDesv = desvAbs.reduce((acc,val) => acc+val);
	return sumDesv/input.length;
}
console.log(dam([34,29,39,34]));