1226545 - fibonacci series example is incorrect

Status: RESOLVED FIXED

(Developer Documentation Graveyard :: JavaScript, defect)

Description

[amit17thawait]

User Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2490.71 Safari/537.36

Steps to reproduce:

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Iterators_and_generators#Advanced_generators

The fibonacci generator implementation is incorrect.


Actual results:

The actual result of the solution given for fibonacci generates sequence as :
1, 1, 2, 3, 5, 8, 13, 21, ...


Expected results:

The actual fibonacci sequence starts from 0 but not 1. Its even stated incorrectly in the wikipedia.

The first number for fibonacci series start with 0 and not 1. You can contact any mathematics scientist and they will also say it starts with 0 and not 1.

The correct solution should be :

function* fibonacci(){
  var fn1 = 0;
  var fn2 = 1;
  while (true){  
    var current = fn1;
    fn1 = fn2;
    fn2 = current + fn1;
    var reset = yield current;
    if (reset){
        fn1 = 0;
        fn2 = 1;
    }
  }
}


Please refer these links for reference :
1) https://www.quora.com/Does-the-Fibonacci-sequence-start-with-0

2) http://www.maths.surrey.ac.uk/hosted-sites/R.Knott/Fibonacci/fib.html

3) http://www.maths.surrey.ac.uk/hosted-sites/R.Knott/Fibonacci/fibtable.html