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ENTER↑ is a misnomer, long live ENTER:
07-07-2014, 09:59 PM
Post: #19
RE: ENTER↑ is a misnomer, long live ENTER:
(07-07-2014 07:20 PM)walter b Wrote:  
(07-07-2014 05:37 PM)hansklav Wrote:  The problem is that you, as a seasoned user of RPN, only see one function of ENTER: duplicating a number on (sorry: under) the stack.
How do you know?

Because this is what you wrote in your reply:

(07-07-2014 07:20 PM)walter b Wrote:  (…) ENTER↑ describes what the operation does - it enters a number in the stack. Even the arrow points in the right direction (…)

And you did not mention the other function (digit entry termination).

(07-07-2014 07:20 PM)walter b Wrote:  If you'd take a look to the WP 34S manual instead of telling me what you guess what I see then you'd see how I explain ENTER in the start section ("elementary stack mechanics").

My apologies. I did not realize that you are the author of that decent piece of work! And I must admit that the beautiful lay-out of the WP 34S Owner's Manual was an inspiration for me when writing an RPN Tutorial (to be published soon).

(07-07-2014 07:20 PM)walter b Wrote:  And also HP was aware of that 'novice' problem 40 (!) years ago already: please find below their explanation of 1974.

Ah, the famous RPN Algorithm from HP’s ‘ENTER↑ vs. =’ brochure! In that brochure HP called it ‘a diagram of the RPN method’, but it is a modification of the original RPN Algorithm first published in the HP-35 Operating Manual and later also in the HP-45 Owner's Manual.

That diagram certainly showed clearly the number separation function of the ENTER↑ key. But it has nothing to do with the point I would like to make in this thread about the naming the ENTER key in classical RPN calculators of the future.

However the algorithm depicted in this diagram has another interesting problem: it doesn't work for some quite simple calculations with nested parentheses… Because it was told by HP to start at the left side of the calculation. And then you will soon get stuck (that is: get wrong answers without any warning), unless you have ‘an operational stack of unlimited length’. So the ‘ENTER↑ vs. =’ brochure was the last time HP used this diagram (as far a I know), although it is perfectly valid in the later RPL calculators with (virtually) unlimited stack length.

(07-07-2014 07:20 PM)walter b Wrote:  I won't go into your other insinuations.

I didn’t mean to insinuate anything, just wanted to make my point most clearly. If you felt that as insinuations, again: my apologies.

(07-07-2014 07:20 PM)walter b Wrote:  Please do better research next time.

I’ll do my best!

Hans
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RE: ENTER↑ is a misnomer, long live ENTER: - hansklav - 07-07-2014 09:59 PM



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