Re: Fun with Unbounded Rational Numbers

["Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>]

On 04/09/2017 09:15 AM, Paul Rubin wrote:
>
> did you remember to recompute Y in your loop?  i.e.
>
>          M := Two * X;
>          Y = X * X - 2     -- <---- this might have been missing?
>          X := X - Y / M;

The implementation is

       X := R / Two;

       All_Iterations : for I in 1 .. 15 loop
          Y := X ** 2 - R;

          exit All_Iterations when abs Y < A;

          M := Two * X;
          X := X - Y / M;
       end loop All_Iterations;

       return X;

where R is the argument and A the accuracy.

-- 
Jeff Carter
"This trial is a travesty. It's a travesty of a mockery of a
sham of a mockery of a travesty of two mockeries of a sham. ...
Do you realize there's not a single homosexual on that jury?"
Bananas
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