(12C) Signum Function

[Albert Chan]

(03-03-2019 04:59 PM)Thomas Klemm Wrote:  There's no "uncertainty" when it comes to rounding numbers.
Though this may be related it doesn't explain what's going on.

Turns out, there is nothing to explain. I found a counter-example ...
My post on square, following by square-root round-trip is wrong

Example, on HP-12C, x = Pi + 0.04 = 3.181592654

3.181592654^2 ≈ 10.1225318160, rounded-up-to 10.12253182

√10.12253182 ≈ 3.18159265463, rounded-up-to 3.181592655

Ratio of x / √(x²) = 0.9999999997 ≠ 1