From:	dontmailme AT iname DOT com (Steamer)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: modf BROKEN ??
Date:	Tue, 01 Aug 2000 18:43:13 GMT
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

Radical NetSurfer wrote:

> At 5.0, 6.0, etc, Fract display as "1.0" because of a rounding error
> in the   printf   output.  Its only an "optical illusion", and if 
> %3.21 is used, you won't see it.
> 
> the question is obvious:
> HOW do I maintain a %3.3f  output, but NOT get the 
> 1.0 "optical illusion"  ???

This is not an obvious question at all, especially as you didn't
use %3.3f in your previous post.

One way to print out the fractional part without this rounding
problem is to use sprintf to print the entire number to a buffer,
and then print out the fractional part from there.  Or (assuming
your numbers are positive and not too big) you could do this sort
of thing:

    ((unsigned long)(1000.0*f+0.5)) % 1000

and print that out with leading zeroes.  In fact, depending on
what you're doing, it may be better not to use floating-point
numbers at all - just use suitably scaled integers.

S.

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