On Wed, 7 Jul 2021 at 00:51, Dean Rasheed <dean.a.rash...@gmail.com> wrote: > 10. half_round(21) == 11 :: 20 >> 1 = 10 > > The correct result should be 10 (it would be very odd to claim that > 10241 bytes should be displayed as 11kb), but the half-rounding keeps > rounding up at each stage. > > That's a general property of rounding -- you need to be very careful > when rounding more than once, since otherwise errors will propagate. > C.f. 4083f445c0, which removed a double-round in numeric sqrt().
Thanks. I've adjusted the patch to re-add the round bool flag and get rid of the rightShift field. I'm now calculating how many bits to shift right by based on the difference between the unitbits of the current and next unit then taking 1 bit less if the next unit does half rounding and the current one does not, or adding an extra bit on in the opposite case. I'll post another patch shortly. David
