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JavaScript JavaScript Numbers The Math Object Create a Random Number

MD MONIRUZZAMAN
MD MONIRUZZAMAN
6,130 Points

Adding 1 inside

What is the difference between

const dieRoll = Math.floor(Math.random()*6) +1;

const dieRoll = Math.floor(Math.random()*6 +1 );

2 Answers

Steven Parker
Steven Parker
231,269 Points

Since the "floor" function only affects the fractional part of a value, it makes no difference if a whole number is added before or after. So those two statements will perform exactly the same.

One thing I still am not clear on is why in the video, he says not to use Math.ceil for the die example because it could return a zero. How is this possible? Doesn't "Math.random()" return a number between 0 and 1? Even if the random number is .000001, that would express to a 1, would it not? I've tried referring to the notes on Mozilla which state "The Math.ceil() function always rounds a number up to the next largest whole number or integer.". I guess I'm missing something....

EDIT: Disregard, it seems I missed the part where he says it could gen a number from zero up to, but not including 1.

To answer the question from Zachery Smith, if you use Math.ceil it will round 0.000001 to 1 and then add 1 making 2 the lowest possible roll, and round anything greater the 5.0 to 6. Then add 1 making 7.

boi
boi
14,242 Points

Good one Scott!