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JavaScript

Posted by Victor Gordian
Victor Gordian
4,656 Points

Math floor and math random

function alertRandom() {

var randomNumber = Math.floor( Math.random() * 6 ) + 1;

alert(randomNumber); }

math.floor function rounds up anything (0 - .99) that math.random takes out then it will multiply by 6 and then add 1?

1 Answer

Jonathan Grieve
MOD
Jonathan Grieve
Treehouse Moderator 91,254 Points
Jonathan Grieve
Jonathan Grieve
Treehouse Moderator 91,254 Points

Hi Victor,

The random method actually outputs a random number between 0 and 1 but that has a fixed decimal point number rather than a whole integer value. (i.e. not precisely 1 or 0). So what floor() does is gives us that random value. But it'll always be 0.

So that's what we multiply it by a value 6 and then add 1 to it. Since it always rounds down we won't get a possible 6 output by leaving it as * 6. Adding +1 will allow us to get a possible output of 6.

Hope this helps. :)