[fpc-pascal] Why this evaluates on "if" wrong ?
daniel.mantione at freepascal.org
Sun Oct 28 19:08:09 CET 2007
Op Sun, 28 Oct 2007, schreef Milan Marusinec:
> Hello folks,
> This one looks pretty elementary, but to my big surprise
> it doesn't work as I would expect.
> I'd like to ask FreePascal compiler creators, how can I safely
> evaluate double variables in case like this.
> Sample program with comment is in attachement ...
If you do on a hand calculator:
... you will see:
If you multiply again with 3, you will see:
... and not 1.00000000000.
There is a similar issue here. The value "0.4" cannot be stored exactly in
a computer, therefore it is rounded.
This behaviour normal and while annoying, it is simply how things work
in the digital world, you will have to work around it.
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