From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Fortran / C compiler precision and code pack
Date:	1 Mar 2001 13:02:26 GMT
Organization:	Aachen University of Technology (RWTH)
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To:	djgpp AT delorie DOT com
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>>If your problem is with 14.399996 being printed instead of 14.4,
>>that's normal: REAL variables only have about 6.5 digits of
>>precision.  Try using DOUBLE PRECISION instead.

> Thanks, it seems to be ok. 
> But was it a bug, I have newer seen before in my long life?

It was not so much a bug, but a an error in your expectation about the
program's behaviour. You'ld have to learn a bit more about Fortran to
see how to get the behaviour you expected. And a bit more about
numerical computation in general to see why doing this kind of stuff
with a datatype like REAL is a bad idea --- professional software of
this type would usually count pennies (or even fractions of pennies),
not pounds, and store everything in INTEGER or even INTEGER*8
variables.

-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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