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JavaScript

brandonlind2
brandonlind2
7,823 Points
Posted by brandonlind2
brandonlind2
7,823 Points

Could someone explain the ( ) in javascript?

Could someone explain this ( ) in javascript not as in functions but as in for exmaple this random number function

function randNum(topNum,BottomNum);
var randomNmuber= Math.floor(Math.random() *
 (topNum- bottomNum)//< what are these brakets?
) +bottomNumber;

1 Answer

Bryan Peters
Bryan Peters
11,996 Points
Bryan Peters
Bryan Peters
11,996 Points

Those are used for mathematical order of operations.

In this case, calculate the difference between top num and bottom num to have the range value BEFORE multiplying by the random number.

So, if math.random is 0.5, top num is 10, and bottom num is 1:

0.5 * (10-1) = 4.5 instead of 0.5 * 10 - 1 = 4