Question

We all know good old Math.random(). It returns a random floating point number between 0 and 1.

What I can’t seem to find any evidence about is if zero or one is exclusive or inclusive.

I know that if they are inclusive, the probability of hitting either one of these values is seriously low.

But I can’t help but wonder if I should wasting an if statement looking for it or not.

In my current scenario zero is not a problem, but one is.

var __rand:uint = Math.floor( Math.random() * myArray.length );
var result:String = myArray[__rand];

if the 1 in Math.random() is exclusive, then I will know that will NEVER be 1, and therefore __rand could never equal myArray.length and should always be below it.. But just wasn’t sure if I should waste time in some performance critical code if I should account for it.

PS: The code above is NOT the performance critical code, just an example

Basically, just 2 simple questions.
1) Is returning one impossible or possible.
2) If possible, is it worth accounting for it.

Answer 1

Math.random will return a number between 0 and (1 exclusive). Never will return a 1.