Question

I am using

var min = -13;
var max = 13;
var random = Math.floor(Math.random() * (max - min + 1)) + min;

but it returns ALL numbers(random) between -13 and 13. how can i get it to generate a random number between -13 to -4 exluding -3 , -2, -1, 0 , 1 ,2 ,3 and including 4 to 13.

Answer 1

Get a random number between 1-10 and add 3, to get one between 4-13:

random = Math.ceil(Math.random() * 10) + 3;

Generate a random between 0-1. If it’s 0, make the number negative:

random = (Math.floor(Math.random() * 2) == 0) ? 0 - random : random;

JSFiddle showing working copy:

http://jsfiddle.net/adamh/cyGwf/