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Marshall wrote:
> On Feb 28, 9:20 am, Bob Badour <bbad..._at_pei.sympatico.ca> wrote: >
> > > My problem with this examples has always been the limitations > of floating point numbers. Consider (1,1). It is exactly representable > in cartesian form, but not in polar form; the radius is sqrt(2), an > irrational. > > However, I had not considered: "How does the dba do that without > disrupting any of the applications" previously; I'll have to think > about that some more. > > >
> > > In the case of lossy compression, I feel strongly that it is a logical > matter, and cannot be abstracted away. The choice of compression > ratios and algorithms needs to be under user/application control, > not dba control.
Surely a video application would not try to map sqrt(2) to an individual pixel without a notion of rounding or somesuch. Without somesuch, I presume a polar possrep would either disallow that polar value or equate it a cartesian coordinate that exists. Don't ask me how to implement it, though. I still don't understand how the RM all by itself can decide equality/identity.
p Received on Wed Feb 28 2007 - 12:57:31 CST