Re: Fun with Unbounded Rational Numbers

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

On 04/09/2017 11:18 PM, Paul Rubin wrote:
> "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org> writes:
>> 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;   ...
>
>
> Can you instrument this loop to check how many iterations are actually
> being executed, and preferably how long each one takes?

As I said in another post, the thing that was taking the time was subtracting R 
(2) in the calculation of Y. I made some improvements to the addition algorithm 
and now it calculates sqrt(2) to within 0.000001 very quickly, in 4-5 
iterations. The result is 665857/470832.

-- 
Jeff Carter
"I didn't squawk about the steak, dear. I
merely said I didn't see that old horse
that used to be tethered outside here."
Never Give a Sucker an Even Break
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