The correct way to compare floating point numbers is ...

Moritz, in general that's problematic.

The calculation error doubles with every calculation step, no matter how big epsilon is, you can construct a counterexample, where your rule breaks.

Consequently you have to limit the numbers of calculations before you can tell which epsilon is save!

IMHO that's a ridiculous big effort compared to the normal possibility to stay integer right away by multiplicating the fractions away.

532.2 - 23.2 
 
=>
 
5232 - 232 = 5000 
 
=> 500.0

[download]

Cheers Rolf

In reply to Re^2: eq vs == by LanX
in thread eq vs == by spikeheap

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