generate n primes javascript code example

Example: hwo to make ana array of prime numbers in javascript

function sort_prime(num) {

  var prime_num1 = [],
      prime_num2 = [];
  for (var i = 0; i <= num; i++) {
    prime_num2.push(true);
  }
  for (var i = 2; i <= num; i++) {
    if (prime_num2[i]) {
      prime_num1.push(i);
      for (var j = 1; i * j <= num; j++) {
        prime_num2[i * j] = false;
      }
    }
  }

  return prime_num1;
}

console.log(sort_prime(5))