In Wikidata, there is an existing paradigm to model the defining formula of a particular mathematical or scientific concept, along with ways to model quantities that are used to calculate/evaluate the formula. In many cases, however, the defining formula is not something that can be calculated. It's just a definition that gives a relation. In these cases, it doesn't make sense to use calculated from (P4934), thus we propose an analaogous property "defined in terms of."
Comment The proposed property will be applicable to fields outside of mathematics, so I welcome suggestions particullarly with regards to the domain and allowed values. The-erinaceous-one (talk) 04:21, 2 September 2020 (UTC)
Comment Could the scope of calculated from (P4934) be generalized to "other terms mentioned in defining formula"? That's how I have understood it so far, say for magnetic flux density (Q30204) where the to-be-defined item does not appear simply on the left-hand-side and the formula can't be solved for it. How exactly would we choose between P4934 and the property proposed here? Toni 001 (talk) 08:37, 2 September 2020 (UTC)
@Toni 001: Modifying calculated from (P4934) might be a good alternative to creating a new property, especially since, as you note, the distinction between calculated from (P4934) and the proposed property would be fuzzy. One concern with going that route is that calculated from (P4934) might currently be used in cases where the defining formula is not given. Also, changing the label and description could be confusing for a lot of editors and would require updating the labels and discriptions in all the languages. But those are all switching costs and would be outweighed by the long term benefits of better-designed properties.