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Fwd: Re: What is this principle called: "I' send data inmy UOM

• From: rjelliffe <rjelliffe@allette.com.au>
• To: <xml-dev@lists.xml.org>
• Date: Sat, 10 Sep 2011 16:53:31 +1000

 I think the main principle is grouped under the head "information 
 preservation" (or "information retention"): you don't throw away 
 anything until you can prove some-one won't need it. (Being 
 "conservative' in what you send means being conservative in what you 
 thow away, in this case.)

 This does not mean that you cannot *also* send the data in a converted 
 format:
   <width cm="33.33333">1/3m</width>
 The recipient can choose which it likes. If in doubt, do both (if this 
 won't cause integrity problems for later editing.)

 In commercial publishing systems, the most common way to handle this 
 situation, however, is neither to preserve the information as a fraction 
 nor to convert it to decimal. It is to re-express the value as integers 
 values against some very small common unit which is some reasonably 
 accurate fraction of all the bases and demonimators desired. See EMUs 
 (http://www.oreillynet.com/xml/blog/2007/04/what_is_an_emu.html) for 
 example.


 Cheers
 Rick Jelliffe
 

• Follow-Ups:
  • Re: Re: What is this principle called: "I' send data in myUOM and you convert it, as needed, to your UOM"?
    • From: Greg Hunt <greg@firmansyah.com>