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From: Jan Burse <janburse@fastmail.fm>
Newsgroups: comp.lang.java.programmer
Subject: Re: higher precision doubles
Date: Sat, 06 Aug 2011 21:24:25 +0200
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Stefan Ram schrieb:
> Jan Burse<janburse@fastmail.fm>  writes:
>> IEEE allows to internally calculate with additional bits.
>> Is it possible to have awailable these ops? Like an add
>> with this higher precision? How could we store such a
>> result? Would there be a wrapper like Double?
>
>    See also:
>
> http://en.wikipedia.org/wiki/Strictfp
>
>    .
>

Motivating example, in Go we have:

     func main() {
	x := math.Sin(2*math.Pi)
	fmt.Printf("x = %.30f, is zero = %v\n", x, x == 0)
     }

     x = 0.000000000000000000000000000000, is zero = true

In Java we have:


     public static double zero1() {
         return Math.sin(2*Math.PI);
     }

     public static double zero2() {
         return StrictMath.sin(2*StrictMath.PI);
     }

     public static void main(String[] args) {
         System.out.println("zero1="+zero1());
         System.out.println("zero2="+zero2());
     }

     zero1=-2.4492935982947064E-16
     zero2=-2.4492935982947064E-16