[fpc-pascal] Freepascal Floating Point Issue

[Daniel Franzini]

Long story short: not every single real number have an *exact*
representation in the computer. You have to live with that and learn the
limitations and pitfalls of floating point calculations.

On Mon, Aug 21, 2017 at 7:42 PM, Ralf Quint <freedos.la at gmail.com> wrote:

> On 8/21/2017 3:34 PM, Daniel Franzini wrote:
> > It might be the case (I didn't do the math) that 999.999 doesn't have
> > an exact representation in IEEE-754 double-precision format, so the
> > best you get is an aproximation (a pretty good one, btw).
> Just use WriteLn (Draw_GX_Min:3:16) and you get no mystery digits
> anymore...
>
> In pretty much any programming language/compiler, if you print more
> digits than the precision of the used variable defines, you will get
> random numbers after the defined precision.
> This is not something FreePascal specific, any C/C++ compiler for
> example will do the same thing. People need to learn what limitations
> come along with floating point variables/calculations...
>
> Ralf
>
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-- 
Daniel

"Let us change our traditional attitude to the construction of programs.
Instead of imagining that our main task is to instruct a computer what to
do, let us concentrate rather on explaining to human beings what we want a
computer to do." (Donald Knuth)

"Yes, technogeeks can be funny, even if only to each other." (
http://www.boogieonline.com/revolution/science/humor/)"

"Man is driven to create; I know I really love to create things. And while
I'm not good at painting, drawing, or music, I can write software."
(Yukihiro Matsumoto, a.k.a. ``Matz'')
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