Re: RPN (was Re: TI-83+)

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Re: RPN (was Re: TI-83+)

> I grabbed the closest book to me, opened it up and
>what did I see?

Well, I saw this equation:

   n
------
2^(n-1)-1

Notice that in the book there were no parentheses (I had to use parentheses
because of font limitations)

On the TI, you would enter this equation as:

n / ( 2 ^ ( n - 1 ) - 1 )

In RPN, you would enter this equation as:

n [spc] 2 [spc] n [spc] 1 - yx 1 - /

Now, when I look at that original equation, I see n 2 n 1 - yx 1 - /.  I don't
see n/(2^(n-1)-1).  Some people see other the latter but not the former.  It
doesn't mean that I'm more intelligent becase I see the former; it just means I
look at it differently.  Do realize, however, that the TI version took 13
keystrokes while the RPN version took only 12.

And as far as your equation is concerned,

( 2 + 3 ^ 2 ) ^ ( 1 / 4 )

the exact keystrokes needed on the HP48 is

2 [spc] 3 [purple shift] x^2 + 1 [spc] 4 / yx

Notice again that the TI notation requires 13 keystrokes whereas the RPN
notation requires 11.

>Remember, the R in RPN
>stands for reverse.

Yes, the R in RPN does stand for reverse.  Astute observation.  That's because
a mathematician from Poland who's name I won't attempt to spell came up with a
prefix notation in the 1950s.  Computer operators found that postfix notation,
or RPN, fit perfectly with the operations of chips.  They found it more
intuitive that the arguments of an operands be placed before the operand,
because a 2 argument operand cannot function without its two arguments.  In
fact, TI calculators can do nothing to the infix user input without first
converting it to RPN.

English is my first language.  When I speak French, since I am not as fluent in
French as I am in English, it requires a "mental conversion".  This does not
mean that English is better than French.  To say so would be absurd.

It's the same way with TI notation versus RPN.  Some people find TI notation
intuitive while others find RPN intuitive.  This doesn't make one group smarter
than another.  It's simply a matter of preference.   Either group can learn the
other form of notation just as easily as the other group originally learned it.
 In fact, the only sign of lower intelligence would be the person who
arbitrarily refused to learn the other notation.

Objectively, RPN requires fewer keystrokes.  This is true and proven.

Preference is subjective.

>BTW Jeremy, you had offered to provide objective support for your
>opinions.  Were you able to come up with any yet?

I wrote what I felt was objective support for my opinions.  If you feel
otherwise, find some objective disproof of my opinions.

Jeremy

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