Re: Greatest Common Divisor

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От Vik Fearing
Тема Re: Greatest Common Divisor
Дата
Msg-id 535e8b2f-325b-788a-9dd9-58b170f45f98@2ndquadrant.com
обсуждение исходный текст
Ответ на Re: Greatest Common Divisor  (Dean Rasheed <dean.a.rasheed@gmail.com>)
Ответы Re: Greatest Common Divisor
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On 04/01/2020 20:08, Dean Rasheed wrote:
> On Sat, 4 Jan 2020 at 17:55, Vik Fearing <vik.fearing@2ndquadrant.com> wrote:
>> On 04/01/2020 10:37, Dean Rasheed wrote:
>>> BTW, there is actually no need to restrict the inputs to integral
>>> values because GCD is something that has a perfectly natural extension
>>> to floating point inputs (see for example [1]). Moreover, since we
>>> already have a mod(numeric, numeric) that works for arbitrary inputs,
>>> Euclid's algorithm just works.
>>> [...]
>>> If it were more work to support non-integer inputs, I'd say that it's
>>> not worth the effort, but since it's actually less work to just allow
>>> it, then why not?
>>
>> Okay, I allow that now, but I've still left it for lcm.  I can't find
>> anything anywhere that defines lcm for floating point (I do find it for
>> fractions) and the result of abs(a*b)/gcd(a,b) certainly doesn't match
>> "lowest" in the examples I tried.
>>
> Here's another article on the subject:
> https://www.math-only-math.com/hcf-and-lcm-of-decimals.html


Yeah, my eyes weren't aligning the decimal points properly.


Attached version frees up lcm to work on non-integrals.  Thanks for your
input!

-- 

Vik Fearing


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