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Re: Keen eyes

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Den lördag 16 januari 2016 kl. 23:30:48 UTC+1 skrev Chris Angelico:
> On Sun, Jan 17, 2016 at 9:23 AM,  <jonas.thornvall@gmail.com> wrote:
> > function factor_it(i){
> > prime=true;
> > sqroot=Math.floor(Math.sqrt(i));
> > for (j=2;j<sqroot;j++){ k=i/j; prime=!Number.isInteger(k); if (prime) {return prime}}
> > return prime;
> > }
> 
> A couple of potential problems here. The first thing that comes to
> mind is that floating point inaccuracy is going to bite you long
> before the numbers "seem huge" to someone who's thinking about 2**53.
> The second is an off-by-one error: a perfect square may come up as
> prime.
> 
> Check for those and see how it looks.
> 
> Also, check your double-use of the 'prime' variable, which also
> appears to be global here.
> 
> ChrisA

Thank you Chris your comment resolved it double use of j in two different functions and loops.

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Keen eyes jonas.thornvall@gmail.com - 2016-01-16 14:23 -0800
  Re: Keen eyes Chris Angelico <rosuav@gmail.com> - 2016-01-17 09:30 +1100
    Re: Keen eyes jonas.thornvall@gmail.com - 2016-01-16 14:55 -0800
    Re: Keen eyes jonas.thornvall@gmail.com - 2016-01-16 15:25 -0800
      Re: Keen eyes Steven D'Aprano <steve@pearwood.info> - 2016-01-17 18:10 +1100
        Re: Keen eyes Ian Kelly <ian.g.kelly@gmail.com> - 2016-01-17 00:37 -0700
        Re: Keen eyes Paul Rubin <no.email@nospam.invalid> - 2016-01-16 23:52 -0800
        Re: Keen eyes Chris Angelico <rosuav@gmail.com> - 2016-01-17 19:25 +1100
          Re: Keen eyes BartC <bc@freeuk.com> - 2016-01-17 11:17 +0000
            Re: Keen eyes Chris Angelico <rosuav@gmail.com> - 2016-01-17 22:32 +1100

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