HP41 rounds inaccurately
Posted: Sun May 21, 2023 2:09 am
Highly likely this issue is known since long and well described somewhere, for me it is a new finding (or I've forgotten I once did know about it long time ago).
There are situations where the HP41 shows numbers rounded wrong. Example: 3^201 yields 796841966627624308016343966107338880487700357960183487923724885217277472703906548983154097132003 what is "just few digits too large" for to be displayed correctly, assumedly almost all pocket calculators show this result rounded only, or, less pleasing, truncated. Up to now I was convinced, "my" HP41 rounds correctly beyond all doubt. But look at the display showing a. m. result:
FIX 7 -->
FIX 8 --> That is for sure not what I expected, the number of displayed digits remains the same, so what is the "need" to change it? If not a bug it's at least a nasty surprise.
Another example: compute 3 1/x 3E66 *
FIX 8 -->
FIX 9 -->
Other machines? Your exercise.
There are situations where the HP41 shows numbers rounded wrong. Example: 3^201 yields 796841966627624308016343966107338880487700357960183487923724885217277472703906548983154097132003 what is "just few digits too large" for to be displayed correctly, assumedly almost all pocket calculators show this result rounded only, or, less pleasing, truncated. Up to now I was convinced, "my" HP41 rounds correctly beyond all doubt. But look at the display showing a. m. result:
FIX 7 -->
FIX 8 --> That is for sure not what I expected, the number of displayed digits remains the same, so what is the "need" to change it? If not a bug it's at least a nasty surprise.
Another example: compute 3 1/x 3E66 *
FIX 8 -->
FIX 9 -->
Other machines? Your exercise.