[QUANTITY] Choosing default accuracy/units values

[Pierre Didelon]

Hi Patrick,

Patrick Dowler wrote:

> I agree that default units and default accuracy/error should follow the same
> rules. However, to be successful the VO really needs to get people (force them 
> if necessary) to not be lazy, so I would prefer making specification of units 
> and accuracy mandatory (in the schema) and have some special values that can 
> be easily used, like <unitless> and <exact> and <uknownUnits> and 
> <unknownAccuracy>. There should be no default value.
> 
Isn't specila tag values <units>Number</units>, <accuracy>exact</accuracy>,
<units>unknown</units> and <accuracy>unknown</accuracy> better  than
special tag names?
> Yes, this does potentially increase the size of the serialised form, but the 
> benefits outweigh the cost, IMO. And sure, those unknown tags are especially 
> large, but they should be rare (who wants data with those tags in there?) and 
> providers of such tags/data will be discouraged by their usage stats :-)

A question is what will be the main usage of Quantities, always used as components
in big doc., or as elementary information to specify searching criteria.
> 
> my 2c,
> 
> Pat
> 
Regards,
Pierre