K: Likely for a "constant mode," where the calculator uses one operand as a constant for repeated >calculations (e.g., multiplying several numbers by the same value).
The other position is likely "normal mode," disabling this feature.
Middle Switch ("A/2/4/6" etc.):
This could control decimal rounding or precision:
"A" might stand for "automatic" mode.
"0, 2, 3, 4, 6" refers to the number of decimal places displayed or used in calculations.
"F" likely stands for "full precision," using all available decimal places.
Right Switch ("Σ" setting):
Σ: Likely enables a "summation mode," where the calculator automatically adds results to a running total (useful for bookkeeping or repetitive additions).
The other position disables this mode.
Being Swedish the "constant mode" seems likely as we often used k (for "konstant") in school math to represent a constant (e.g. for the slope of a line).
Until I saw your post, I was going to guess the A,0,2,3,4,6,F switch would switch it into different numerical bases. Like, if you wanted to do math in binary, switch to the "2" position. "0" (or maybe "A") would be base 10. "F" would be hexadecimal. But what you have definitely makes more sense.
This looks mostly right. The precision slider is definitelyprobably only for the output, not calculations. The (up | 5/4 | down) is (always round up | round 5+ up and 4- down | always round down)
What I'd like to know is how the A and F settings are different.
Auto to me (if A is Auto) sounds like it'd truncate unnecessary digits (4 or 4.0 instead of 4.0000) maybe? Whereas if F is Full then you'd get full precision?
Idk seems logical but not especially useful, probably not a great guess.
I can say that A seems to be Auto in the way you think but I haven't figured out what criteria it has for this automation. Maybe there's a way I could figure it out. I'm not a maths kind of guy (had pretty bad teachers in school) so it's all honestly above my head. Shamefully enough.
I noticed that too, but they are coprime with one another and they aren't divisible by or into 10, so they would definitely create repeating digits. Could've used 1/3 for the same effect though.
I just tried and it's a pi approximation, which makes more sense.