Re: Mixing OO and DB

On Feb 23, 2:41 am, "Dmitry A. Kazakov" <mail..._at_dmitry-kazakov.de> wrote:
> On Fri, 22 Feb 2008 15:39:06 -0800 (PST), Marshall wrote:
> > On Feb 22, 2:34 pm, "Dmitry A. Kazakov" <mail..._at_dmitry-kazakov.de>
> >>>>> It appears you are somehow claiming that multiplication
> >>>>> is not defined on computable numbers.
>
> >>>> Sure. Multiplication (addition, subtraction, division) is incomputable and
> >>>> thus cannot be defined.
>
> >>> The claim "multiplication is uncomputable" is amusing.
>
> >> Really? Show me a DFA model of multiplication in R. Let's laugh together.
>
> > Oh, so there are additional hidden qualifiers
>
> Come on, don't you have a computer at work? These are comp.xxx groups!

The term "computable number" and "real number" are well defined, familiar terms in mathematics, with distinct meanings. The term "multiplication" refers to many different functions. The fact that I am using these terms according to accepted common practice, and you are making terms up as it suits you and refusing to define them, makes the conversation unproductive.

> > to your unqualified
> > claim that multiplication is uncomputable? You mean specifically
> > multiplication on the reals, despite the fact that you were
> > responding to a statement of mine that was specifically
> > about only the computable reals?
>
> No, that does not save you. You cannot provide any non-trivial finite
> subset of reals closed on multiplication.

Since you challenge is trivially easy on the face of it, I expect there must be additional, hidden qualifiers that you have not stated, which you will only trot out once I answer. How unappealing.

Nontrivial subsets of reals closed on multiplication:

  N, Z, Q

  forall n in N, Z mod n

All contain 2 and are closed under multiplication, and the multiplication operator is computable. For the last one, the multiplication operator is O(1) in size. You might be familiar with a particular instance of this where n=2^32.

Okay, now tell me how my answers don't meet your criteria a, b, and c which you will only now reveal. Or better yet, don't.

> >> Nobody ever claimed that a circle is not an ellipse.
>
> > No one except you:
>
> > On Feb 15, 3:13 am, "Dmitry A. Kazakov" <mail..._at_dmitry-kazakov.de>
> > wrote:
>
> >> Circle value is not an ellipse value. These have different types.
>
> Sure.
>
> > It was my entree into the thread, to chastise you for making broad
> > unqualified statements such as that one.
>
> It seems that you do not understand difference between a model and the
> thing being modeled.
>
> Circle value /= circle
> Ellipse value /= ellipse
> Circle value /= Ellipse value
>
> "Value" in this context is a CS term. So "circle value" is. That reads: "a
> value that serves a model for some circle."
>
> Because, obviously, CS /= Geometry (would you challenge this too?), while
> "circle" is a term of the latter (objections?), therefore, you cannot claim
> them same. It is a logical fallacy.

Meaningless tripe. Unsubstantiated assertions using terms in ways inconsistent with common usage but without specific definitions. You say they are different because they are different. You justification is "geometry." You might as well say "human knowledge."

It is clear enough at this point that you are almost certainly not having the discussion in good faith, and that even if you are, you inability to state either your assumptions or your definitions makes you incapable of debating productively.

Good day to you sir.

Marshall Received on Sat Feb 23 2008 - 19:53:09 CET