Re: Natural keys vs Aritficial Keys
From: Bob Badour <bbadour_at_pei.sympatico.ca>
Date: Sat, 23 May 2009 01:43:38 -0300
Message-ID: <4a177eb6$0$23742$9a566e8b_at_news.aliant.net>
>
> ....
>
> The point has nothing to do with rationals, some decimal fractions are
> irrational. I never said a cpu should express exact values, rather it
> should express the exact same values people who are accustomed to
> decimal arithmetic or traditional slide-rules come up wiith. To talk
> otherwise is to argue for Betamax.
Date: Sat, 23 May 2009 01:43:38 -0300
Message-ID: <4a177eb6$0$23742$9a566e8b_at_news.aliant.net>
paul c wrote:
> toby wrote:
>
>> On May 22, 9:10 pm, paul c <toledobythe..._at_oohay.ac> wrote: >> >>> Bob Badour wrote: >>> >>>> paul c wrote: >>>> >>>>> Bob Badour wrote: >>>>> >>>>>> paul c wrote: >>> >>> ... >>> >>>>>>> Oh, just remembered another one - fixed-point decimal arithmetic! >>>>>> >>>>>> What do you need that for? >>>>> >>>>> To get the same answer as the lawyer with his amortization tables. >>>> >>>> Integers are integers no matter the base. >>> >>> Sure they are, but I was talking about decimal points. Eg., it bugs me >>> that the most widely-used (that doesn't mean most popular) cpu >>> 'architecture', Intel's, can't express the fraction 2/5 exactly. >> >> >> If expressing exact rationals is what you want, then that is trivially >> done using integer arithmetic - as is fixed point decimal. Hardware >> decimals, which essentially died with the VAX, don't help you express >> rationals. >> >> Have a play with these: >> http://gmplib.org/ (see mpq for rationals) >> http://docs.sympy.org/
>
> ....
>
> The point has nothing to do with rationals, some decimal fractions are
> irrational. I never said a cpu should express exact values, rather it
> should express the exact same values people who are accustomed to
> decimal arithmetic or traditional slide-rules come up wiith. To talk
> otherwise is to argue for Betamax.
But integers do that. All one has to do is shift the decimal point, which people using slide rules have tons of experience doing. Received on Sat May 23 2009 - 06:43:38 CEST