use math.ceil() and math.floor() example

Example 1: javascript ceiling

var ceiling1 = Math.ceil(4.7); //5 
var ceiling2 = Math.ceil(-3.4); //-3

Example 2: How does Math.ceil work

Math.ceil(x); //This equals the next whole number after x. X must be a double.

//Example use:
x = Math.ceil(x);
//Now x is equal to x rounded up.