And how do I calculate the value of this "epsilon" that is being mentioned

As sectokia's first post indicated, Machine::Epsilon provides machine_epsilon(). It is dependent on the $Config{doublesize}, but for 64-bit, the value that sectokia quoted is the value. It is the maximum error, relative to the appropriate power of two.

The value of that is the same as ulp(1) (from my Data::IEEE754::Tools), where ulp is the Unit in the last place. But really, ulp(value) is the easier way to figure out the exact ULP size for a given value, and you know that the "real" value is somewhere between +/- 1 ULP (actually, I think +/- 0.5 ULP, really) from the value stored in the 64-bit double float.

In reply to Re^5: what did I just see..? by pryrt
in thread what did I just see..? by ishaybas

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