How would I get it where every time it generates a random number it adds it onto a variable in javascript?

Question

How would I make it where every time it generates a random number it adds it on to a variable called Num my code is below.

function Generate() {
    var Num;
    var RanN = Math.floor((Math.random()*10)+1);
    for (var i=0;i<4;i++) {
        Num += RanN;
    }
}

Accept a `Num` as an argument and return it from your function — zerkms, Mar 04 '14 at 23:19
What do you want to do with `Num`? Does the value need to be accessible from somewhere? — Ted Hopp, Mar 04 '14 at 23:20
And you might need to put the `var RanN = Math.floor((Math.random()*10)+1);` inside the loop if you are hoping to get a different number four times — Sebastien, Mar 04 '14 at 23:21
@alex: immutability (and pure functions) is the way :-) PS: alex is back, yay — zerkms, Mar 04 '14 at 23:22
@Ted Hopp I want to add a random number every time it makes a random number in the loop and add it to Num — CDW, Mar 04 '14 at 23:22
I moved the math random into the loop but when I have it alert me after the loop is over and it says NaN — CDW, Mar 04 '14 at 23:24

score 0 · Answer 1 · answered Mar 04 '14 at 23:24

If you're trying to generate a random number i amount of times and add it to a pre-existing number, you'll want something like this:

function Generate(startNum, iterations) {
   for (var i=0; i<iterations; i++) {
      startNum +=  Math.floor((Math.random()*10)+1);
   }
   return startNum;
}

And you would use it like this (if you want to add ten randomly generated numbers):

var num = 0;
num = Generate(num, 10);

Here's a fiddle.

score 0 · Answer 2 · answered Mar 04 '14 at 23:25

0

Here is what I think the OP want:

function Generate(Num) {
    for (var i=0;i<4;i++) {
        Num += Math.floor((Math.random()*10)+1);
    }
    return Num;
}

answered Mar 04 '14 at 23:25

Sebastien

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score 0 · Answer 3 · answered Mar 04 '14 at 23:30

0

The answers are slightly different in structure to your function. If you want to fix what you have (seeing that you have moved the random function into the loop), just change var Num; to var Num=0;, which will fix the NaN error (because you can't add a number to something that is not defined, because it is Not a Number)

answered Mar 04 '14 at 23:30

Chris M

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You're correct in your suggestion, but he's not going to get anything back the way his function is currently written. It's going to add the same randomly-generated number four times and then *poof*. @Sebastien and I have both given him something he can actually use and build on. – DeeDee Mar 04 '14 at 23:34
@DeeDee, fair point, and your answers are great, I just thought that it hadn't been made explicit that the thing crashing it was the above. CDW had moved the random() line following Sebastien's comment, so I wanted to help CDW to fix their own code. – Chris M Mar 06 '14 at 08:09

score 0 · Answer 4 · edited May 23 '17 at 12:28

0

If what you want is a random int you could use:

function getRandomInt (min, max) {
    return Math.floor(Math.random() * (max - min + 1)) + min;
}

console.log(getRandomInt(1111, 9999));

You can find more info here.

edited May 23 '17 at 12:28

Community

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answered Mar 04 '14 at 23:36

a--m

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How would I get it where every time it generates a random number it adds it onto a variable in javascript?

4 Answers4