separar por comas cifra de miles
function formatNumber (num) {
var decimales = num % 1;
if(decimales == 0)
var x = Math.round(num); //Si no tiene decimales, le quita los 0s
else
var x = num.toFixed(2); //REDONDEA A DOS DECIMALES
return x.toString().replace(/(\d)(?=(\d{3})+(?!\d))/g, "$1,")
}
console.info(formatNumber(1240.5)); // 1,240.5
console.info(formatNumber(1000240.5)); // 1,000,240.5