WP 34S vs. DM42 decimal128 differences?

[Paul Dale]

An interesting approach, one I had considered when I added the range reduction to these functions. My concern, then and now, is that e.g. \( \frac{\pi}4 - x \) cannot be represented exactly and that this could change the result in some cases. You are dividing by \( 2\pi \) so the later range reduction will be exact, but this division step and the later inverse would be where the equivalent error occurs.

It is possible that at some level of extended precision, the errors become insignificant. Determining and proving this wouldn't be trivial.

It's quite a difficult problem Still, it is an approach that's worth chasing.


Pauli