Wikidata:Property proposal/Base Units

Base Units[edit]

Originally proposed at Wikidata:Property proposal/Generic

Done: derived from base unit (P12571) (Talk and documentation)

Description	Property that lists the different units that a unit is derived from, would be useful to add a qualifier for the exponent of each unit ie. metre per second (Q182429) → second (Q11574) → -1.
Data type	Item
Domain	unit of measurement (Q47574)
Allowed values	instance of (P31)unit of measurement (Q47574)
Example 1	metre per second (Q182429) → metre (Q11573) metre per second (Q182429) → second (Q11574)
Example 2	pound-foot (Q16859309) → foot (Q3710) pound-foot (Q16859309) → pound (Q100995)
Example 3	cubic metre (Q25517) → metre (Q11573)
Example 4	newton (Q12438) → kilogram (Q11570) newton (Q12438) → metre (Q11573) newton (Q12438) → second (Q11574)
Planned use	Add better definitions of units and relations to other units
See also	unit symbol (P5061), conversion to SI unit (P2370), conversion to standard unit (P2442)

Motivation[edit]

Units are important in many fields and it is important to have some kind of structure to help add relationships between units. The more structured knowledge there is for units the more useful quantities can become and be better used together. -I is chan (talk) 01:54, 29 October 2022 (UTC)[reply]

Discussion[edit]

Comment It seems like has part(s) (P527) is currently sometimes used for that, e.g. metre per second (Q182429)has part(s) (P527)metre (Q11573). What is your motivation for introducing a new property instead of using has part(s) (P527)? --Push-f (talk) 02:32, 30 October 2022 (UTC)[reply]

has part(s) (P527) doesn't seem like a proper use case for this because for metre per second (Q182429)has part(s) (P527)second (Q11574) technically second (Q11574) is being removed from the unit rather than being "a part of" it, perhaps it could have a negative quantity (P1114) quantifier? -I is chan (talk) 12:51, 30 October 2022 (UTC)[reply]

I think has part(s) (P527) fits fine. Units that are composed of several other units are also called "compound units". E.g. [1] says "speed is a compound unit as it is defined using both distance and time". So the other units are all part of the definition. --Push-f (talk) 20:42, 1 November 2022 (UTC)[reply]

Support has part(s) (P527) shouldn't be used for this. -wd-Ryan (Talk/Edits) 15:59, 30 October 2022 (UTC)[reply]
Why not? ChristianKl ❪✉❫ 20:19, 1 November 2022 (UTC)[reply]
@Wd-Ryan: can you explain why you think it should not be used like this? ChristianKl ❪✉❫ 10:35, 28 May 2023 (UTC)[reply]
@ChristianKl:, would you like to give your opinion? @Wd-Ryan: could you please clarify the comments above. Regards, ZI Jony ^(Talk) 06:22, 25 January 2024 (UTC)[reply]
I don't believe that these should be considered parts. For instance, parts of a day could be hours, minutes, etc.. If that is true, parts of kilometers per second would be meters per second, etc.. I think Dexxor's concern is valid anyway. -wd-Ryan (Talk/Edits) 22:29, 25 January 2024 (UTC)[reply]

Comment What should a qualifier stating the exponent of the unit be called? -I is chan (talk) 19:20, 30 October 2022 (UTC)[reply]
Support --Gymnicus (talk) 08:25, 10 May 2023 (UTC)[reply]
Support, an important property for science.--Arbnos (talk) 22:01, 11 January 2024 (UTC)[reply]

Oppose in its current form. This property is not well-defined. For example, the unit tesla (Q163343) has several possible definitions. You could avoid this by only allowing the SI base units as values, but then it would be essentially the same as ISQ dimension (P4020). It also wouldn't allow you to establish a link between pound-foot (Q16859309) and foot (Q3710). I think a better alternative is named after (P138)foot (Q3710) or something akin to: