Is there some way (module, idiom) to represent real numbers such that the same real number gets the same floating point representation, so that I can use them as hash keys for the approach above?
Are you concerned about it being portable, or just consistent on the same hardware? You've got some answers that should help with consistency.

If you want it portable, you may need something like Math::BigFloat, which, IIRC, should be portable.

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re: Histogramming -- Floating point numbers as hash keys by QM
in thread Histogramming -- Floating point numbers as hash keys by dokkeldepper

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