RPN calculator, with operators and operands separate? Sounds counter-intuitive to me. What's the advantage I'm missing?
P.S.
Hi Liam and all,
Is RPN really written with operators and operands separate? If so, that is a bit odd. The name, so far as I know, comes from a notation developed in Poland in the 1920's (+/- 5 years) for writing logical formula without brackets. But it does not quite separate out the two classes of symbols.
Writing 'v' for or and '&' for and,
A v ((B & C) v D)
would go over as:
vAv&BCD
and
(A v B) & (C v D)
as
&vABvCD
The advantage is 1) everything can be unambiguously written without '(' characters, and thus, 2) parsing code is a bit easier to write.
By analogy, I had always assumed that Polish Arithmetic would read
(2 + 3) - 1 and 2 + (3 - 1)
as:
-+231 and +2-31
I further assumed that RPN would simply reverse this. If that isn't true, I think I need to go investigate the origins of the name.
Best to all,
Brian vdB
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