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Sander, > In udunits2-common.xml there appears to be a definition for the logarithmic > unit for 'bell'. However, the symbol used for this seems to be 'BW' instead > of 'B'. Is there a rationale behind this or is this just a typo? There's no definition of the unit "Bell" in the UDUNITS-2 database. This is because the Bell unit is meaningless by itself: it always has to be referenced to a reference level. This is why the Bell units that are in the database have one or more characters following the "B". The Bell units in the database are ones with well-known reference levels and symbolic abbreviations. > Consistency-wise, the item below is Bm (and not BWm). Based on documents such > as "Guide for the Use of the International System of Units (SI)" > <http://physics.nist.gov/cuu/pdf/sp811.pdf> I would expect just 'B' and 'Bm' > to be available. > > I also checked, but there does not seem to be another symbol 'B' that would > conflict with using 'B' for bell. Like I said, a "B" by itself would be meaningless. There would be no way to convert values in that unit specification to values in another, compatible specification. You could add a Bell unit to the database as a local addition. I doubt that others would be able to use it, however, for the reason I gave. > Best regards, > Sander Niemeijer > S[&]T, The Netherlands Regards, Steve Emmerson Ticket Details =================== Ticket ID: IEB-391154 Department: Support UDUNITS Priority: Normal Status: Closed