On 2012-12-19 16:56, Daniel Kinzler wrote:
On 19.12.2012 16:47, Gregor Hagedorn wrote:
Daniel confirms (in separate mail) that Wikidata indeed intends to convert any derived SI units to a common formula of base units.
Example: a quantity like "1013 hektopascal", the common unit for meterological barometric pressure (this used to be millibar), would be stored and re-displayed as 1.013 10^5 kg⋅m−1⋅s−2
Converted and stored, yes, but not displayed. For display, it would be converted to a customary/convenient unit according to the user's (or client site's) locale, using a bit of heuristics to get the scale (order of magnitude) right.
Of course, in wikitext, the desired output unit can be specified.
Actually we have 3 different use cases of values:
1. Internally in the data base 2. On wikidata.org 3. On other projects like WP and also WM external projects
SI shall be used internally (1.)
On 2. the user can decide what he wants.
On 3. either some standard setting of the MW-project says, what is desired or the article's author.
Via API (also 3.) you should be able to choose: * precision * displaying of accuracy * unit
-- Marco