In UCUM, the period '.' is only used as a multiplication operator, thus ?2.7? means always 2 ? 7 and is not equal to 27/10. The use of curly brace is already part of UCUM systax, so it would be already compliant with it.
I haven't yet found any mailing list in HL7 which deals with this aspect.. Regards, leonardo Thomas Beale-3 wrote: > > On 26/05/2011 16:48, Leonardo Moretti wrote: >> Hi all, >> I thought a lot on your proposal. >> >> If we want to use pseudo-units (non-UCUM terms), then we have to be able >> to >> distinguish when a term is in UCUM syntax. For example g/m2.7 is a valid >> UCUM string, but it is interpreted as (g/m^2) * 7 and not as g/(m^2.7), >> because in UCUM ?.? is the symbol for multiplication operator. >> So ?units? attribute should become a sort of code phrase, with the >> information on adopted syntax. Otherwise we can have an ambiguous syntax. > > I am surprised that precedence does not force the reading of the full > number following a '^', or a unit like 'm' when the '^' is inferred. I > will have to look at my own UCUM parser to see what it does! > >> As alternative, if we want to go on using only UCUM syntax, we could >> express >> this pseudo-unit (and not standard units) with the so-called annotation, >> wrapped in curly braces (see >> http://aurora.regenstrief.org/~ucum/ucum.html#section-Character-Set-and-Lexical-Rules, >> section 6). In this case, we can adopt {g/m2.7} safely, remaining >> compliant >> with the UCUM syntax. > > I actually think that is a good idea. Have you looked for a mailing list > or place in HL7 where you can make that proposal? > > - thomas beale > > _______________________________________________ > openEHR-technical mailing list > openEHR-technical at openehr.org > http://lists.chime.ucl.ac.uk/mailman/listinfo/openehr-technical > > -- View this message in context: http://old.nabble.com/Unable-to-express-an-unit-of-measurements-in-UCUM-syntax-tp31494533p31715342.html Sent from the openehr-technical mailing list archive at Nabble.com.
