No, they each have a separate power of two in their canonical floating-hex (%a) representation

Yes, that was careless thinking ("thoughtless thinking" might be a better term) on my part.

So yes, we've probably gone far enough on this tangent.

Agreed.
However, there were a couple of things in your last post that I couldn't quite follow.
I'll mention them here, and you can respond if you like - but I think we both understand what we're doing, so please feel free to not respond at all. (I think you've probably already put more effort into this thread than you would have been expecting.)

IIUC, in respect to the value 0.3, you wrote "whereas the ULP is 3.5e-18", yet I believe it's actually 5.551115123125783e-17.

You also wrote "I have to subtract 23 ULP from the canonical 1.03 representation before it doesn't round up to 1.03 displayed".
I take it that was in relation to the difference between 1.03000000000000003e+00 and 1.02999999999999980e+00 .
Firstly, I think you should have been looking at the "%.16e" or "%.17g" (not "%.17e") formatting of the values.
Secondly, by my way of thinking, the difference between 0x1.07ae147ae147bp+0 and 0x1.07ae147ae147ap+0 is 1 ULP, irrespective of what the chosen decimal formatting shows.

Anyway, thanks for the time you've taken in clarifying and correcting.

Cheers,
Rob

In reply to Re^8: what did I just see..? by syphilis
in thread what did I just see..? by ishaybas

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