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ammarkhan
Front End Web Development Techdegree Student 21,661 Pointsunderstanding RandomNumber function
So, i was trying to understand the code for function in the movie and end up doing this
function RandomNumber(upper){
return Math.random(Math.floor(upper) + 1);
}
and it worked. Now i am trying to understand why did this work and why my numbers are in decimals?
1 Answer

Steven Parker
215,356 Points
Math.random doesn't take an argument.
Providing one does not cause an error, but it is ignored. So your function is equavalent to: "Math.random()
". And by itself, that returns decimal numbers less than 1.
If you wanted a function to return random integers chosen from a set going from 1 to a specified upper limit, you could write it this way:
function RandomNumber(upper) {
return Math.floor(Math.random() * upper) + 1;
}