Left vs. right side arithmetic keys

[Peter Klein]

Does anyone know why HP changed the placement of the basic arithmetic operation keys from the left side to the right side? And also changed the order of the keys from (- + x /) to (/ * - +)? The change appears to have occurred with the Voyagers and the HP 48s.

[Valentin Albillo]

.
Hi,

It's been asked any number of times before, you just have to search for "arithmetic keys" and you'll find a number of answers, e.g.

Does anybody know why HP change or quit using the layout of the earlier models keyboards?

V.

[Peet]

(12-26-2023 09:14 AM)Peter Klein Wrote:  The change appears to have occurred with the Voyagers and the HP 48s.

The Voyagers didn't start the change, they followed the classic layout (left on portrait, right on landscape - see 67 vs 97), the change appears when HP started with algebraic and hybrid (rpn/algebraic) calculators.

[Paul Dale]

The right hand placement and ordering feels far more natural when I use them.
I'll note that I first learned with left hand operators, so it's not a mental early learning condition.

As to why, no idea. Maybe the folks at HP realised their errant ways and adjusted


Pauli

[Thomas Klemm]

(12-26-2023 10:37 AM)Peet Wrote:  left on portrait, right on landscape - see 67 vs 97

I never noticed that. Thanks for the hint.

[J-F Garnier]

(12-26-2023 10:37 AM)Peet Wrote:  The Voyagers didn't start the change, they followed the classic layout (left on portrait, right on landscape - see 67 vs 97), the change appears when HP started with algebraic and hybrid (rpn/algebraic) calculators.

Well, I think it's not the portrait/landscape aspect that is so important, but the handheld/desktop distinction.

The HP desktop calculators used the /, x, -, + key order since the HP-9100 (1968), first on the left of the numeric pad but quickly moved to the right side with the HP-9830 (1972).
The HP-97 (1976) indeed reused the same desktop layout (and key order !), then later the Voyager series and the HP-71B, and finally the HP-28C and descendants.

J-F

[Peter Klein]

Thanks for the comments and the link. I’m left-handed, so I use the calculator with my right hand and write with my left. I like the newer arrangement better, even though my first HP, the HP25, used the old arrangement. Today, when I use the ‘25, I find my index finger swaying first to the right and then to the left with each arithmetic operation.

Massimo ends his posts with: "-+×÷ ↔ left is right and right is wrong"

Which reminds me of this:
“The opposite of left is right.
The opposite of right is wrong.
So anyone who’s left–
Is wrong – right?”
(Stephen Sondheim, “Anyone Can Whistle,“ 1964)

I wonder if Sondheim ever used an HP calculator…. ;-)

[Matt Agajanian]

Hi all. So that’s it’s an equal opportunity thread, even with TI’s beginning with the Datamath/2500, their 4-banger keys were (and still are) right-sided. Which reminds me of the last chapter of their Fingertip Math book which shows how to operate the calc just like you would with a typewriter (e.g. no looking at the keyboard).

[johnb]

I find that the difference between operators on the left versus the right don't throw me nearly as much as the difference between "-+×÷" and "÷×-+" does.

I generally am looking at the calculator when I'm operating it, so that probably accounts for left/right. (I'm left handed... and I also have a bad habit of looking at my fingers when I'm playing piano or organ --- LOL, when playing Theatre Organ, if you don't already know the music by heart when doing registration changes and such, you're already sunk!)

Most of my machines are Voyagers, Pioneers, or 48's. (And a 35s which follows the Pioneer pattern... roughly.) So when I'm using one of the classics, I'm always dividing when I meant to add, and so forth. Why doesn't my eye pick up on the operator before my finger gets there?


PS: To muddy the analytical waters more, I'm a touch typist and don't even have to look down for punctuation like []{}\\// and so forth. So, go figure!

[Steve Simpkin]

I recently ran across a blog post by Steve Leibson which has the following quote from Tom Osborne regarding the arithmetic key placement choices on the early HP hand held models.

"One last thing. We placed the four basic arithmetic functions on the left side of the keyboard so that right-handed people would not cover up the keys with their hand. Also, the + key is in line with the center row of numeric keys because it is the most frequently used arithmetic key and that placement is the easiest to access by someone who enters data by touch, i.e. not hunt-and-peck.

I think HP went awry when they moved the keys to the other side. Convention is safe, but often wrong. Convention is often the process of propagating a bad idea."

More from Tom Osborne on the Design of the HP65

[Matt Agajanian]

Thanks for that HP-65 article. Quite informative.

[Albert Chan]

(05-31-2024 05:15 PM)Steve Simpkin Wrote:  "Convention is safe, but often wrong. Convention is often the process of propagating a bad idea."

Which side is the conventional way of +-*/ placement? Why is it bad?

[Steve Simpkin]

(05-31-2024 05:15 PM)Steve Simpkin Wrote:  I recently ran across a blog post by Steve Leibson which has the following quote from Tom Osborne regarding the arithmetic key placement choices on the early HP hand held models.

"One last thing. We placed the four basic arithmetic functions on the left side of the keyboard so that right-handed people would not cover up the keys with their hand. Also, the + key is in line with the center row of numeric keys because it is the most frequently used arithmetic key and that placement is the easiest to access by someone who enters data by touch, i.e. not hunt-and-peck.

I think HP went awry when they moved the keys to the other side. Convention is safe, but often wrong. Convention is often the process of propagating a bad idea."

More from Tom Osborne on the Design of the HP65

Here are two previous blog posts from Steve Leibson regarding the HP-35:

IEEE Recognizes HP 35 Calculator as a Milestone: The Day Spreadsheet Management Failed

More Details on the HP35’s Early Development


There are also the following videos:

Interview with Dave Cochran about the HP 35 Calculator

Interview with Tom Osborne, inventor of the desktop scientific calculator