On Wed, Dec 19, 2012 at 11:23 AM, Daniel Kinzler < daniel.kinzler@wikimedia.de> wrote:
On 19.12.2012 08:34, Nikola Smolenski wrote:
While at it, why not separate longitude and latitude? There are items
that only
have one, f.e. http://en.wikipedia.org/wiki/Prime_meridian#
I'd argue that the prime meridian does not have a location. And I think it would be bad to make longitude or latitude optional in a geo-coordinate data type.
What about the North and South Poles?
What I wanted to say. Additionally, in some cases historical units are
not
accurate or accurately known, so possibly we won't even be able to make
the
conversion.
I don't think we can sensibly support historical units with unknown conversions, because they cannot be compared directly to SI units. So, they couldn't be used to answer queries, can't be converted for display, etc - they arn't units in any sense the software can understand. This is a solvable problem, but would add a tremendous amount of complexity.
Won't we need lots of units that are not SI units (e.g. base pairs, IQ points, Scoville heat units, $ and €) and can't readily be translated into them? Why would historical units with unknown conversions pose any more problem than these?
Avenue