They example you used cheats by using a number that's rational in decimal but irrational in binary. If they had picked a number that's irrational in both (e.g. 1000001/999999 instead of 1000001/1000000), both the BFP and the DFP calculations would suffer from the same problem.

DFP helps in some cases, but it might not be the best solution.

In reply to Re^3: Decimal Floating Point (DFP) and does Perl needs DFP? by ikegami
in thread Decimal Floating Point (DFP) and does Perl needs DFP? by flexvault

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