User talk:Stuchalk

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Instance of unit of measurement

[edit]

Hello. I noticed that you are adding statements of the form x -> instance of -> unit of measurement, like this one here. Note that this statement is already implied by the presence of other statements, like x -> instance of -> coherent SI unit (Q69197847). Therefore I'm wondering whether those additional statements you added are actually necessary.

Best wishes and welcome to Wikidata. Toni 001 (talk) 09:49, 1 June 2021 (UTC)[reply]

The assignment of 'unit of measurement' was already on over 600 entities that are units, even though yes it could be inferred by classification. In terms of a SPARQL query to retrieve all the units of measurement it seemed easiest to do it this way. I will look into writing something that uses the classification to pull out all units of measurement. One thing that would be really useful on each Wikidata page is to see what other information is inferred about the entity in question... Stuart Chalk (talk) 10:50, 1 June 2021 (UTC)[reply]

Here is a query which retrieves all units (over 6000):
select distinct ?unit ?unitLabel where {
  ?unit wdt:P31 / wdt:P279* wd:Q47574 .
  service wikibase:label { bd:serviceParam wikibase:language "[AUTO_LANGUAGE],en" }
}
Try it!
There are various other things that could be inferred: For instance, kilometre measures length, and radius is a subclass of length, which means that kilometre can also be used to express a radius. Toni 001 (talk) 08:27, 2 June 2021 (UTC)[reply]

Thanks for the query. I had created one myself to get the subclass of 'unit of measurement' and then get the instances under those, but this is clearly better and more succinct :) Stuart Chalk (talk) 10:46, 2 June 2021 (UTC)[reply]