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Re: are int, float, long, double, side-effects of computer engineering?

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From Dennis Lee Bieber <wlfraed@ix.netcom.com>
Subject Re: are int, float, long, double, side-effects of computer engineering?
Date Tue, 06 Mar 2012 21:51:46 -0500
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On Tue, 06 Mar 2012 16:29:10 -0500, Calvin Kim <reader@calvinkim.org>
declaimed the following in gmane.comp.python.general:


> I can see your point. But that's not simply true. In my case and many 
> others, such issue was addressed during first week of introductory 
> programming classes. I was naively thought "computer = precision" and I 
> was stunned to find out the inaccuracy of computer calculations.
> 
> But as you experienced, I also stumble upon some people (specially Java 
> only programmers) who were not aware of it.
>
	It wouldn't surprise me to find out that modern CompSci degrees
don't even discuss machine representation of numbers. In contrast I
recall having an assignment, in my assembly class I think, to emulate
the floating point operations using integer operations and bit
manipulation. Somewhat fun as the Sigma-6 used a rather unusual
"exponent" (base-16... a normalized binary mantissa could have up to
three 0-bits)

> Maybe it's because I'm not in scientific community, that I learned to 
> live with such side-effects. Because 99.99% of computer users and 

	And, as I learned "science", results should not exceed the precision
of the input -- if the input (physical measurements) only had 5
significant figures, any output beyond 5 significant figures was noise.
Granted, some of the internal number crunching might need
double-precision (orbital position propagation, say), but the printed
results would only be to the level of the initial measurements.
-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
        wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/

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Thread

are int, float, long, double, side-effects of computer engineering? Xah Lee <xahlee@gmail.com> - 2012-03-05 17:11 -0800
  Re: are int, float, long, double, side-effects of computer engineering? Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-03-06 02:14 +0000
  Re: are int, float, long, double, side-effects of computer engineering? Westley Martínez <anikom15@gmail.com> - 2012-03-05 19:17 -0800
  Re: are int, float, long, double, side-effects of computer engineering? Tim Roberts <timr@probo.com> - 2012-03-05 21:26 -0800
    Re: are int, float, long, double, side-effects of computer engineering? Xah Lee <xahlee@gmail.com> - 2012-03-05 22:34 -0800
      Re: are int, float, long, double, side-effects of computer engineering? "Russ P." <russ.paielli@gmail.com> - 2012-03-06 00:02 -0800
      Re: are int, float, long, double, side-effects of computer engineering? Chiron <chiron613.no.spam.@no.spam.please.gmail.com> - 2012-03-06 10:10 +0000
        Re: are int, float, long, double, side-effects of computer engineering? Roy Smith <roy@panix.com> - 2012-03-06 08:49 -0500
      Re: are int, float, long, double, side-effects of computer engineering? Calvin Kim <reader@calvinkim.org> - 2012-03-06 16:29 -0500
      Re: are int, float, long, double, side-effects of computer engineering? Westley Martínez <anikom15@gmail.com> - 2012-03-06 16:53 -0800
      Re: are int, float, long, double, side-effects of computer engineering? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-03-06 21:51 -0500
      RE: are int, float, long, double, side-effects of computer engineering? "Prasad, Ramit" <ramit.prasad@jpmorgan.com> - 2012-03-07 19:05 +0000
  Re: are int, float, long, double, side-effects of computer engineering? Chiron <chiron613.no.spam.@no.spam.please.gmail.com> - 2012-03-06 10:00 +0000
  Re: are int, float, long, double, side-effects of computer engineering? rusi <rustompmody@gmail.com> - 2012-03-06 19:25 -0800
    Re: are int, float, long, double, side-effects of computer engineering? "Russ P." <russ.paielli@gmail.com> - 2012-03-07 14:02 -0800
      Re: are int, float, long, double, side-effects of computer engineering? John Nagle <nagle@animats.com> - 2012-03-13 22:32 -0700
  Re: are int, float, long, double, side-effects of computer engineering? Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-03-13 10:40 +0000

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