From:	Endlisnis <s257m AT unb DOT ca>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Floating/fixed point
Date:	Sat, 12 Sep 1998 13:12:36 -0300
Organization:	NBTel Internet
Lines:	24
Message-ID:	<35FA9D74.E138AD72@unb.ca>
References:	<000601bdde5b$f3b72c20$f54e08c3 AT arthur>
NNTP-Posting-Host:	fctnts07c20.nbnet.nb.ca
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Arthur wrote:
> Although floating point math is just as fast as integer math on a Pentium,
> it sucks on anything less than a Pentium, on any AMD processor (apart from
> the K6-2) and any Cyrix processor (apart from the Cyrix MediaGX chip). Also
> conditionals and integer-float conversion are unfeasibly slow on any chip.
	I don't know where you got your info, but floating point math is MUCH slower
than int's even on a Pentium.  Pentium's do floating point math much faster
than 486/387 chips did, but they are still slower than integer.  You can't add
2 floats in 1 clock cycle.

> However, a 32-bit float (32.32) is much more accurate than a 32-bit (16.16)
> fixed number.
	That is very misleading (or wrong).  32-bit float's (also known as double's)
aren't 32.32.  You make it sound like there are 32 bits before the decimal and
32 bits after (9 digits.9 digits).  double's are 12 digits of precision with a
base 10 exponent that can range from +-308.

-- 
     (\/) Endlisnis (\/)
          s257m AT unb DOT ca
          Endlisnis AT GeoCities DOT com
          Endlis AT nbnet DOT nb DOT ca

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