On 17/11/2014 12:47, Ian McNicoll wrote: > Hi Thomas, > > RM function to retrieve a magnitude expressed as a particular unit. > > from my previous email ... > > I think we could add something at reference model level to say give me > this quantity in 'x' units, performing the conversion at server level > where possible or return null. This could also be supported in AQL > since it would just be another RM attribute/function? > > magnitude.inUnit['mg'] > > I think this is, roughly speaking, what FHIR is doing >
well, it's not a reference model thing inasmuch as it's not an information model concept at all, but a knowledge service concept, relying on some database of units that knows about canonical forms, conversions etc. This is what things like the UCUM service do, via an API. I wouldn't want to make the RM dependent on specific functions of such an API; I think the most that the RM should assume (as it does right now in fact) is that the units are in UCUM syntax. - thomas