View source for Testwiki:Property proposal/defined in terms of

=== {{TranslateThis | anchor = en
| en = other items in defining formula
<!-- |xx = property names in some other languages -->
}} ===
{{Property proposal
|status			=  withdrawn
|description		= {{TranslateThis
 | en = mathematical objects used in the defining formula, for which "{{P|4934}}" does not apply
<!-- | xx = descriptions in other languages -->
 }}
|subject item           = <!-- item corresponding to the concept represented by the property, if applicable; example: item child (Q7569) for property child (P40) -->
|infobox parameter	= <!-- Wikipedia infobox parameters, if any; ex: "population" in [[:en:template:infobox settlement]] -->
|datatype		= item <!-- put datatype here (one of: item, external-id, string, media, coordinates, monolingual text, multilingual text, time, URL, number, geo-shape, tabular, lexeme, form, sense, mathematical expression, or a possibly new one) -->
|domain			= {{Q|246672}}<!-- entity type (item, property, lexeme, form, sense) and types of items that may bear this property; give QIDs if possible -->
|allowed values		=  {{Q|246672}} <!-- type of linked items (Q template or text), string pattern (regex if possible), list or range of allowed values, etc. -->
|source			= <!-- external reference URL, Wikipedia list article, etc. -->
<!-- you should provide 3 examples at least-->
|example 1		= {{Q|207643}} → {{Q|55091432}}, {{Q|126736}} (c.f. {{Statement|Q207643|P2534|<math>T(\alpha \mathbf{x} + \beta \mathbf{y}) = \alpha T(\mathbf{x}) + \beta T(\mathbf{y}), \quad \forall \alpha, \beta \in \mathbb{R}, \forall \mathbf{x}, \mathbf{y} \in \operatorname{dom}(T)</math>}})
|example 2		= {{Q|339444}} → {{Q|203484}}  (c.f. {{Statement|Q339444|P2534|<math>\Delta u=0</math>}})
|example 3		= {{Q|731894}} -> {{Q|98828598}}  (c.f. {{Statement|Q731894|P2534|<math>\|fg\|_1 \le \|f\|_p \|g\|_q</math>}})
|example 4		= {{Q|1195250}} -> {{Q|189000}}, {{Q|11408}}  (c.f. {{Statement|Q1195250|P2534|<math>\nabla\cdot\mathbf{B}=0</math>}})
|example 5      = {{Q|165474}} -> {{Q|30242895}} (c.f. {{Statement|Q165474|P2534|<math>\forall x,y\colon x\star y=y\star x</math>}})
|example 6      = {{Q|844980}} -> commutator bracket?  (c.f. {{Statement|Q844980|P2534|<math>[[a,b],c]=[[a,c],b] + [a,[b,c]]</math>}})
|planned use            = <!-- what use do you plan to make of the property within the next month -->
|see also               = {{P|2534}}, {{P|4934}}, {{P|7235}} <!-- other, related properties -->
|subpage		= defined in terms of
|topic			= natural science
}}

====Motivation====

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 {{P|4934}}, thus we propose an analaogous property "defined in terms of."

To expand on an example given above, consider {{Q|1195250}}. We have {{Statement|Q1195250|P2534|<math>\nabla\cdot\mathbf{B}=0</math>}}. Clearly, Gauss's law isn't "calculated from" the magnetic field <math>\mathbf{B}</math>, it merely gives a relation between the magnetic and electric fields, so P4934 is not approriate. The proposed property would be thus be used as follows
{{Statement+
|rank=+1
|P=defined in terms of
|V={{Q|11408}}
|qp={{P|P7235}}
|qv=<math>\mathbf B</math>
}}
{{Statement+
|rank=+1
|P=defined in terms of
|V={{Q|189000}}
|qp={{P|P7235}}
|qv=<math>\nabla \cdot</math>
}}
[[User:The-erinaceous-one|The-erinaceous-one]] ([[User talk:The-erinaceous-one|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 04:21, 2 September 2020 (UTC)

===={{int:Talk}}====
{{Ping project|Mathematics}}
{{Ping project|Physics}}

{{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. [[User:The-erinaceous-one|The-erinaceous-one]] ([[User talk:The-erinaceous-one|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 04:21, 2 September 2020 (UTC)

{{comment}} Could the scope of {{P|4934}} be generalized to "other terms mentioned in defining formula"? That's how I have understood it so far, say for {{Q|30204}} 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? [[User:Toni 001|Toni 001]] ([[User talk:Toni 001|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 08:37, 2 September 2020 (UTC)
: {{ping|Toni 001}} Modifying {{P|4934}} might be a good alternative to creating a new property, especially since, as you note, the distinction between {{P|4934}} and the proposed property would be fuzzy. One concern with going that route is that {{P|4934}} 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.
:
: If we do modify {{P|4934}}, I suggest we use "other items in defining formula."  {{ping|Okkn}} as the creator of proposal for {{P|4934}}, perhaps you would like to weigh in on this too.  [[User:The-erinaceous-one|The-erinaceous-one]] ([[User talk:The-erinaceous-one|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 17:37, 2 September 2020 (UTC)
::I can agree with generalizing P4934. I don't think there will be any confusion. --[[User:Okkn|Okkn]] ([[User talk:Okkn|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 06:46, 4 September 2020 (UTC)
::: I added a comment to the [[Property talk:P4934#Widening the scope of this property|property talk page]]. I do {{support}} this generalization. [[User:Toni 001|Toni 001]] ([[User talk:Toni 001|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 09:13, 4 September 2020 (UTC)
::Sounds good indeed. Feel free to edit label/description of P4934 to make sure it's understood by both mathematicians and other contributors. --- [[User talk:Jura1|Jura]] 09:14, 4 September 2020 (UTC)
::: Great, I've modified the label and description of P4934 and have withdrawn this proposal. [[User:The-erinaceous-one|The-erinaceous-one]] ([[User talk:The-erinaceous-one|<span class="signature-talk">{{int:Talkpagelinktext}}</span>]]) 22:28, 4 September 2020 (UTC)