Re: [netmod] Justification for decimal64 over string for floating point values in geo location data?

Christian Hopps <chopps@chopps.org> Tue, 07 July 2020 12:27 UTC

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From: Christian Hopps <chopps@chopps.org>
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Date: Tue, 7 Jul 2020 08:27:19 -0400
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Cc: Christian Hopps <chopps@chopps.org>, NetMod WG <netmod@ietf.org>
To: Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de>
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Subject: Re: [netmod] Justification for decimal64 over string for floating point values in geo location data?
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> On Jul 7, 2020, at 8:18 AM, Juergen Schoenwaelder <j.schoenwaelder@jacobs-university.de> wrote:
> 
> On Tue, Jul 07, 2020 at 07:53:19AM -0400, Christian Hopps wrote:
>> 
>> So do you think it's enough to just use decimal64, and not justify it's use over strings?
> 
> I do not know what 'strings' are here.

Mentioned in the earlier mail

instead of

    "decimal64"

use

    "type string { pattern '[0-9]+(\.[0-9]+)?'; }"

> In the xml and json encodings, everything finally has a string
> representation. But what matters is how the strings are interpreted
> since computers internally often do not use strings when it comes to
> numbers or addresses or ...

But they can operate with arbitrarily precise numbers (e.g., python mpmath, or even decimal with some arbitrarily large precision specified).

Thanks,
Chris.

> 
> /js
> 
> --
> Juergen Schoenwaelder           Jacobs University Bremen gGmbH
> Phone: +49 421 200 3587         Campus Ring 1 | 28759 Bremen | Germany
> Fax:   +49 421 200 3103         <https://www.jacobs-university.de/>
>