Re: SI prefixes with "accepted" units, others

Hours show up as "h" in the commonly used kWh for energy.  Of course SI
uses seconds (and prefix multiples) only as the time unit if I recall.

On Mon, Nov 11, 2024, 05:48 Deyan Ginev <deyan.ginev@gmail.com> wrote:

> Hi Neil, all,
>
> kilo-hours is indeed a sensible unit and has the symbol "khrs".
>
> I see 32 examples of SI Unit symbols with leading "k" in wiktionary, here:
>
> https://en.m.wiktionary.org/w/index.php?title=Category:Symbols_for_SI_units&pagefrom=HG%0Ahg#mw-pages
>
> I suspect there is no "kh" in SI, but "kH" is a "kilohenry" and "kHz" is a
> "kilohertz".
>
> As one idea:
> If one anticipates parsing collisions, a system could support the most
> common unit symbols activating via the ":unit" Intent property,
> but require an explicit :si add-on property to 'intent=":si:unit"', to
> activate the full range of SI possibilities (and safely ignore non-SI
> conflicts).
>
> Another idea would be to require rare/unsupported SI units to carry an
> explicit intent concept, as with intent="kilohour:unit".
>
> Lastly, I suspect this kind of discussion would be better redirected into
> an open MathCAT issue, rather than a closed w3c/mathml issue.
>
> Greetings,
> Deyan
>
>
> On Mon, Nov 11, 2024 at 3:31 AM Neil Soiffer <soiffer@alum.mit.edu> wrote:
>
>> I've started work on making MathCAT handle ":units" and wonder how many
>> of the "accepted" units (and others?) should or should not take SI prefixes
>> (kilo, penta, ...). The units that we came up with are listed in issue
>> #475 <https://github.com/w3c/mathml/issues/475>.
>>
>> For example, does "kh" for "kilo-hour" make any sense? "kt" for
>> "kilo-tonne"? "kl" for "kilo-liter" does make sense though ("liter", or for
>> the British "litre", is not a base unit, it is an accepted unit).
>>
>> Make sure to look at the "other" category at the bottom. Some of them
>> such as bytes and calories take a prefix.
>>
>> Thanks for any guidance you can provide. For posterity, adding your
>> thoughts to the issue would be best, but feel free to reply to this email
>> if that is much easier for you.
>>
>>     Neil
>>
>>