Eleanor McHugh wrote: > On 16 Nov 2009, at 01:12, Todd Benson wrote: >> it's totally reasonable to see something go chaotic because of these >> things. > > This isn't an issue of chaotic behaviour (that has a very fixed > meaning mathematically) but of unnoticeable error. The difference > between 1e10-13 and 2e10-13 matters a lot when working on a system > which needs to be accurate to a resolution of 1e10-14 but not when > working to a resolution of 1e10-4. The additional nine decimal places > tell us nothing meaningful in this latter case as we'll still end up > rounding the result to zero. > >> For a short and unimportant game I'm playing, I wouldn't be upset. >> But, for a game that takes 10's of hours and have it ride my butt >> later at a crucial moment, I might just call that a bug. > > That's not a bug but a fundamental outcome of the nature of binary > coded non-integral numbers. If it gives you the wrong answer, it's a bug. Period. If your representation cannot give you the precision you need for the task at hand, then you need a different representation. Period. The end user doesn't care about your representation -- he cares about getting the right answer. [...] > BCD also > does nothing to resolve the problem of how to represent irrational > numbers such as ¦Ð. No, becuase that's impossible to do with a finite representation AFAIK. If I'm wrong, I would love to know how this can be done. [...] > > Ellie > > Eleanor McHugh > Games With Brains > http://slides.games-with-brains.net > ---- > raise ArgumentError unless @reality.responds_to? :reason Best, -- Marnen Laibow-Koser http://www.marnen.org marnen / marnen.org -- Posted via http://www.ruby-forum.com/.