In this Javascript code using setInterval, why isn't n a different value every time?

Question

n is the same every loop, even though i set it differently every iteration of setInterval. Anyone know a fix or another way I can randomise n every time?

    var n = random(1000, 5000);
let toptimer = setInterval(()=>{
    n = random(1000, 5000);
    obs.push(new obstacle(800, 200, 255));
},n);

Do you want to generate random numbers in a range of 1000 to 5000 is this? — Aks Jacoves, Jun 12 '20 at 16:33
Until we know what `random` is doing, we can't tell you why it's returning the same val. — lux, Jun 12 '20 at 16:33
Does this answer your question? [Why is my variable unaltered after I modify it inside of a function? - Asynchronous code reference](https://stackoverflow.com/questions/23667086/why-is-my-variable-unaltered-after-i-modify-it-inside-of-a-function-asynchron) — Peter O., Jun 12 '20 at 16:38

Shaikh Amaan FM · Answer 1 · 2020-06-12T16:51:28.127

0

The thing you want to achieve cannot be implemented in setInterval as far as I think. You can use setTimeout as following and get the work done.

function foo() {
  var n = random(1000, 5000);
  setTimeout(()=>{
    obs.push(new obstacle(800, 200, 255));
    foo();
  },n);
}

And I hope you have a function "random" like this,

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

edited Jun 12 '20 at 16:51

answered Jun 12 '20 at 16:39

Shaikh Amaan FM

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score 0 · Answer 2 · answered Jun 12 '20 at 16:43

when you call setInterval(func,interval) you set the interval as a parameter and then func is called periodically.

if you want to change duration You should try this

var n = random(1000, 5000);
var exit = false;
var func = () => {
  if(!exit) {
    n = random(1000, 5000);
    obs.push(new obstacle(800, 200, 255));
    setTimeOut(func , n );
  }
}
setTimeOut(func,n);

In this Javascript code using setInterval, why isn't n a different value every time?

2 Answers2