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![Spencer Renfro](https://secure.gravatar.com/avatar/290de00adbb10a59657d8efec59e6b36?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Spencer Renfro
Courses Plus Student 11,133 PointsMath.floor vs. Math.ceil on random number generator
On the random number generator it uses Math.floor, but is there a reason for uses this specifically instead of Math.ceil?
1 Answer
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jb30
44,806 PointsMath.random()
returns a number between 0
inclusive and 1
exclusive, which means that it can return 0
and cannot return 1
. If you use Math.ceil(Math.random() * highValue)
and Math.random()
returns exactly 0
, then you will have Math.ceil(0 * highValue)
, which is Math.ceil(0)
, which is 0
, and 0
is not greater than or equal to 1
.
Laisvūnas Miškinis
6,614 PointsLaisvūnas Miškinis
6,614 Pointsbut why not use Math.round() in something like this:
let randomNum = Math.round(Math.random() * +maxValue);
you will no longer be forced to round only one way which will be more random than floor or ceil.