Math.floor VS Math.trunc JavaScript

Question

Background

I am making a function that receives a positive number and then rounds the number to the closest integer bellow it.

I have been usi

Answer 1

if the argument is a positive number, Math.trunc() is equivalent to Math.floor(), otherwise Math.trunc() is equivalent to Math.ceil().

for the performance check this one and the fastest one is Math.trunc

var t0 = performance.now();
var result = Math.floor(3.5);
var t1 = performance.now();
console.log('Took', (t1 - t0).toFixed(4), 'milliseconds to generate:', result);
var t0 = performance.now();
var result = Math.trunc(3.5);
var t1 = performance.now();
console.log('Took', (t1 - t0).toFixed(4), 'milliseconds to generate:', result);

the result is Took 0.0300 milliseconds to generate: 3 Took 0.0200 milliseconds to generate: 3

so if the arguments are only positive numbers you can use the fastest one.