From: Jim Freeze <jim@...>
Date: 2004-05-13T02:12:08+09:00
Subject: Re: Major Addition Bug?

On Thursday, 13 May 2004 at  2:07:52 +0900, Sean O'Dell wrote:
> On Wednesday 12 May 2004 09:53, ts wrote:
> > >>>>> "S" == Sean O'Dell <sean@celsoft.com> writes:
> >
> > S> raise "false" if ((625.91 + 900.00 + 22.00) != 1547.91)
> >
> >  Well, this is well known
> 
> Well known?  I had no idea this bug existed until I wrote a line of code that 
> double-checked the arithmetic from a different app.  I have code all over 
> doing simple arithmetic like this.  Ruby can't add 3 simple numbers?  I don't 
> mean to be disproportionately negative, but that shakes my faith more than a 
> little.  It's just simple arithmetic.  How old is this bug?  When is it 
> getting fixed?
> 
> 	Sean O'Dell

Sorry, to shake your faith, but consider the following:

  jfn@juno 124 /home/jfn/tmp > cat n.c
  int main()
  {
    printf("%.24f\n", 625.91+900.00+22.00);
  }
  jfn@juno 125 /home/jfn/tmp > ./a.out
  1547.909999999999854480847716


You might want to try the rational library.

Jim

-- 
Jim Freeze
Police:	Good evening, are you the host?
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