recursion - Maximum call stack size exceeded RangeError when recursive function is countable in javascript - Stack Overflow

I've created a script to divide numbers with the chosen number of decimal places. Everything works fine unless I set a huge number of decimal places. The file run via Node.js gives up when the decimal numbers array length reaches ~2400, Chrome gives up on ~1900.

I simplified my code and the script sample below throws Maximum call stack size exceeded RangeError up on ~20000 decimal numbers array length. I thought that this Error throws when the loop or recursive function is called endlessly, but in my case there is a countable number of iterations. It may be a huge number but my module is intended to do the math operations on big numbers.

Why does it happen and Can I avoid this RangeError to occur?

var decimals = [];
var max = 20000;

recurse();

function recurse() {
  decimals.push(Math.floor(Math.random()*10));
  if(decimals.length === max) return;
  recurse();
}

I've created a script to divide numbers with the chosen number of decimal places. Everything works fine unless I set a huge number of decimal places. The file run via Node.js gives up when the decimal numbers array length reaches ~2400, Chrome gives up on ~1900.

I simplified my code and the script sample below throws Maximum call stack size exceeded RangeError up on ~20000 decimal numbers array length. I thought that this Error throws when the loop or recursive function is called endlessly, but in my case there is a countable number of iterations. It may be a huge number but my module is intended to do the math operations on big numbers.

Why does it happen and Can I avoid this RangeError to occur?

var decimals = [];
var max = 20000;

recurse();

function recurse() {
  decimals.push(Math.floor(Math.random()*10));
  if(decimals.length === max) return;
  recurse();
}

• javascript
• recursion
• max
• callstack

Share Improve this question Follow edited Jun 6, 2018 at 1:05 Matus Dubrava 14.5k33 gold badges4444 silver badges6060 bronze badges asked Jun 5, 2018 at 15:43 PawełPaweł 4,53666 gold badges2525 silver badges4242 bronze badges 2

• 2 If this isn't an exercise, it would make more sense as a non-recursive function with a for loop. Then you won't need any outside variables – MCMastery Commented Jun 5, 2018 at 15:50
• @Pawel, I think you will find this Q&A helpful stackoverflow./a/43596323/633183 – Mulan Commented Jun 5, 2018 at 16:12

Add a ment  | 

3 Answers 3

Sorted by: Reset to default 4

No, there is a limit to how many function calls you can place on to the call stack so even if your recursive function has a reachable base case, it will still throw the error if the number of recursive calls is too big.

One workaround would be to use technique called trampoline where you don't perform recursive call directly inside of the function, but insted return a new function that is then executed in a loop until the base case is reached.

Using this technique, your function can perform as many recursive calls as you want because you are not placing more of those function calls to the call stack at the same time, so it will not overflow.

var decimals = [];
var max = 20000;

function _recurse(){
  decimals.push(Math.floor(Math.random()*10));
  if(decimals.length === max) return;
  return () => _recurse();
}

const trampoline = fn => (...args) => {
  let res = fn(...args);
  while (typeof res === 'function') { res = res(); }
  return res;
}

const recurse = trampoline(_recurse);

recurse()

console.log(decimals);

Note that your problem can be solved without the use of recursion in a much simpler way, using loops. For example:

function createRandomSequence(amount) {
  const decimals = [];
  for (let i = 0; i < amount; i++) {
    decimals.push(Math.floor(Math.random()*10));
  }
  return decimals;
}

console.log(createRandomSequence(10));

Just use a regular loop, or something like:

 const random = length => Array.from({ length }, () => Math.floor(Math.random() * 10));

const decimals = random(20000);

Concerning the call stack: see this web page

If it's 20,000 (pseudo random) decimals you're after, you can also use something like:

var maxDecimals = 20000;
var decimals = Array.from({length: maxDecimals})
  .map(v => Math.floor(Math.random()*10));
  
console.log(decimals);