Sorting an Array in Random Order

Question

I'm trying to understand how sorting an array in random order works. So, I found the following code:

var as = ["max","jack","sam"];   var s = as.sort(func);    function func(a, b) {     return 0.5 - Math.random(); }    console.log(s);

my main question is why they use 0.5 not another number? and how it really works

Answer 1

You used

var as = ["max","jack","sam"];   var s = as.sort(func);    function func(a, b) {     return 0.5 - Math.random(); }    console.log(s); 

And here the most important thing is as.sort(func).
func(a,b) will return value in range of [-0.5,0.5].

Because this function return 0.5 - Math.random() and Math.random() will return the float value which is in range of [0,1].
So that your func will return value in range of [-0.5,0.5].

And this mean that sort order will be set increase or decrease. this is random. So your result will be random

var as = ["max","jack","sam"];   var s = as.sort(func);    function func(a, b) {     return Math.random(); }    console.log(s);

var as = ["max","jack","sam"];   var s = as.sort(func);    function func(a, b) {     return 0 - Math.random(); }    console.log(s);

var as = ["max","jack","sam"];   var s = as.sort(func);    function func(a, b) {     return 0.5 - Math.random(); }    console.log(s);