JAVASCRIPT

javascript truncate decimal without rounding

// truncate function
// in this example the default value is 2
function truncate(number, index = 2) {
  	// cutting the number
    return +number.toString().slice(0, (number.toString().indexOf(".")) + (index + 1));
}

// example
console.log(truncate(1234.56789, 3)); // 1234.567

round decimal js

Math.round(num * 100) / 100

javascript decimals without rounding

function getFlooredFixed(v, d) {
    return (Math.floor(v * Math.pow(10, d)) / Math.pow(10, d)).toFixed(d);
}

var x = 2.305185185185195;

document.write(getFlooredFixed(x, 5));