relational quantiy values

[stap-m]

Description of the issue

In #1875 we decided to add a quantity value (hierarchy) that subsumes relational quantity values.

add relational quantity value? (setzt zwei quantities ins verhältnis)

• Bezug von full load hours zu process über process atttribute performance
• market share value zu fraction value
  • area per power value als relational quantity value für specific space requirement
• annual GDP growth
• discount rate
• exchange rate
• inflation rate
• all monetary prices
• purchasing power parity

Ideas of solution

Draft definition for relational quantity value: A relational quantity value is a quantity value that has two or more units in relation to each other as parts.

We also have the fraction value hierarchy. As far as I can see, it contains only quantity values where the units in the fractions are reduced. I'd propose to make it a subhierarchy of relational quantity value.

Workflow checklist

• [ ] I discussed the issue with someone else than me before working on a solution
• [ ] I already read the latest version of the workflow for this repository
• [ ] The goal of this ontology is clear to me

I am aware that

• [ ] every entry in the ontology should have a definition
• [ ] classes should arise from concepts rather than from words

[l-emele]

In my understanding, it should not be two or more units but two or more quantities that relate to each other, because relational quantities can also have their own units. E.g. pressure which relates a force to an area. Thus its quantity value can have the unit N/m². However a pressure can also be expressed in Pascal or Bar which are not composed units. Following the definition proposal, a pressure expressed in N/m² would be a relational quantity value, a pressure expressed in Pascal would not be, despite being equivalent.

[stap-m]

Great, thanks. A relational quantity value is a quantity value that quantifies two or more quantities in relation to each other. Like this?