The Museum of HP Calculators

HP Forum Archive 17

 HP35S vs HP50g KeysMessage #1 Posted by Brad Davis on 30 July 2007, 11:23 a.m. I just bought a HP50g to go along with my trusty 48. I REALLY like it except for one thing (well, actually 2--the battery cover is very poor, IMO, a half a step up from a 28S battery cover. Well maybe a whole step: at least I can use tape to help w/ the 50g...). The keys are just a little too hard for my tastes. How are the 35S keys compared to the 50g? I would rate my 48's keys as absolutely perfect. Also, off the topic: What the heck is up with having x^2 as a second function anyway??!?!?! That was one of the reasons I bought a 33S, but I can't stand only having 4 registers. Edited: 30 July 2007, 11:27 a.m.

 Primary key: x^2 or Square rootMessage #2 Posted by Gene Wright on 30 July 2007, 12:08 p.m.,in response to message #1 by Brad Davis I'm sure this was a tough decision for the design team. The considerations include: In RPN, X^2 can be accomplished by ENTER x, which is two keystrokes and loses a stack level. Having X^2 as a primary key allows for it to be computed with one keystroke, which is more efficient. However, which function is used more often? is Square root used more than X^2? I have no idea, but if Square root is used more often, then it ought to be the primary function rather than X^2. So, part of me wants X^2 to be primary to save a keystroke for efficiency, but if users need Square root 80% of the time, perhaps it should be the primary function. So, what do you guys think? Which is probably used more often? X^2 or Square root?

 Re: Primary key: x^2 or Square rootMessage #3 Posted by Brad Davis on 30 July 2007, 12:38 p.m.,in response to message #2 by Gene Wright Well, we'll all have our opinions, of course. I'm sure the team looked at lots of different options. I am happy overall--just never understood this one little detail. Of course, other users undoubtedly use their wonderful calculators somewhat differently. My take on it: I think I use x^2 about as often as sqrt(x), so I like both as first functions. In this case, I think X should've remained an alpha function and x^2 should go there. Having X as a first function only helps for writing equations faster. I speculate that I'm typical in that I probably spend 10x more time punching through equations than programming equations. Other candidates for second functions to make room for x^2: I use x^2 probably >10x more often than EEX and a little more often than 1/x and x^y. I rarely use SPC and SYMB. I speculate, of course, that I'm more typical than folks who make big time use of those. I could be wrong, though--would be far from the first time. Maybe a future model will allow the user to change the functions. I never use my calculator for programming or plotting (I have Mathcad and Matlab for that), so its primary purpose is punching through big nasty equations. Of course RPL is ideal for that. I use integrals sometimes during virtual work calcs, but that's about it. Of course, this completely skews my perspective. I speculate that many others use them similarly. BTW, I've been using RPN/RPL for 16 years and I'd never thought of duplicating and hitting X again--DUH!! Thanks for mentioning that. I'll just start doing that. It's two keystrokes, but two very fast and convenient ones! Edited: 30 July 2007, 12:47 p.m. after one or more responses were posted

 Re: Primary key: x^2 or Square rootMessage #4 Posted by Kostas Kritsilas on 30 July 2007, 12:46 p.m.,in response to message #3 by Brad Davis The HP-67 had a blue shifted x^2 as well, so this is nothing new. Its just what ends up happening when there are far more functions than keys. The HP-67 had 3 function keys (f yellow, g blue, and h black). The square root was a non-shifted function, but that got over-ridden if a program was read in from a magnetic card, and then also became a shifted function (so did 1/x and y^x). Kostas

 Re: Primary key: x^2 or Square rootMessage #5 Posted by bill platt on 30 July 2007, 12:54 p.m.,in response to message #2 by Gene Wright Without a doubt, square root should be primary, for the simple reason that it is the "difficult" one that you "need" a function for!

 Re: Primary key: x^2 or Square rootMessage #6 Posted by Brad Davis on 30 July 2007, 12:58 p.m.,in response to message #5 by bill platt LOL, guys, I went back and looked and verified that I didn't technically suggest replacing sqrt(x) with x^2 ! I like them both as first functions and see several others that I personally don't use as much.

 Re: Primary key: x^2 or Square rootMessage #7 Posted by Gene Wright on 30 July 2007, 1:03 p.m.,in response to message #6 by Brad Davis Brad, I was really talking about the key layout for the 35s, not the 50g. The 50g is an entire additional story about layout of keys. :-) On the 35s, I'm not sure what primary key function I would move to a shifted function. Certainly, I would not move 1/x or y^x to be shifted functions. The parentheses key really HAS to be primary function not only because making them a shifted function would be a slap in the face to any algebraic users (HP needs those to sell the unit despite what we RPN people might think) but also because of their use in EQN mode.

 Re: Primary key: x^2 or Square rootMessage #8 Posted by Brad Davis on 30 July 2007, 1:15 p.m.,in response to message #7 by Gene Wright Yeah, I agree and I sidetracked completely onto the 50g. My only idea is to move ( to the Sigma+ location. Then again, somebody somewhere probably loves the Sigma+ key as a first function! I'm sure the design team spent many hours debating this kind of thing--it could go on forever. I don't care about the issue as much now that you mentioned to hit Enter, X to square something. Still can't believe I didn't think of that at some point.

 Re: Primary key: x^2 or Square rootMessage #9 Posted by DaveJ on 30 July 2007, 8:57 p.m.,in response to message #6 by Brad Davis Quote: LOL, guys, I went back and looked and verified that I didn't technically suggest replacing sqrt(x) with x^2 ! I like them both as first functions and see several others that I personally don't use as much. That's the problem with programmable calcs like the 35S, the designer has to choose whether to optimise it for programming, or optimise it for general calculations. The 35S has obviously been optimised for use as a programmable calc, so your basic scientific calc keys get shifted and replaced with programming keys and arrow keys. If the 35S had been designed as primarily a scientific calc (as it should have been IMHO for a HP 35 anniversary edition), the keyboard layout would have been a lot different, and more like the 33S, which (chevron issues and big ENTER aside) is a pretty good layout. Dave.

 Re: Primary key: x^2 or Square rootMessage #10 Posted by bill platt on 30 July 2007, 1:36 p.m.,in response to message #2 by Gene Wright More to the point, I'd put other functions on primary status ahead of x^2: STO Ln e^x

 Re: Primary key: x^2 or Square rootMessage #11 Posted by Brad Davis on 30 July 2007, 3:18 p.m.,in response to message #10 by bill platt Yeah, I agree that many would see ln(x) and e^x as higher priority. I didn't think of those because they don't show up very often in my particular line of work.

 Re: Primary key: x^2 or Square rootMessage #12 Posted by Frank Rottgardt on 30 July 2007, 3:41 p.m.,in response to message #2 by Gene Wright x^2 as shifted function was one thing that hits me directly when I saw the first pictures of the 35s key layout. On my 33s I am happy with x^2 being primary. Back then when I was working as surveyor the Pythagoras formula was something I used many many times each day. This in mind x^2 as primary function is very useful. Now, working as mechanical engineer I still have the feeling x^2 occurs more often in formulas than SQRT. So x^2 shifted is not so good in my eyes, but it is certainly a minor disadvantage, and for many others maybe an improvment over the 33s.

 Re: HP35S vs HP50g KeysMessage #13 Posted by Chris Haltiner on 30 July 2007, 1:53 p.m.,in response to message #1 by Brad Davis Quote:How are the 35S keys compared to the 50g? I would rate my 48's keys as absolutely perfect. I wrote about this in my 35s comments post earlier. I find the 35s key tactile feedback to be the closer to my 41CV than any other HP calculator I've owned since then. While the 50g keys are good, I can't make entries on it nearly as fast as I can on the 35s. (This was even after using a much lower keytime value on the 50g.) On the 50g, the harder physical key press as well as the greater key travel are probably factors. I would say the 41CV keys are 10/10. I'd give the 50g a 7/10 and the 35s a 9/10.

 Re: HP35S vs HP50g KeysMessage #14 Posted by Brad Davis on 30 July 2007, 3:21 p.m.,in response to message #13 by Chris Haltiner Thanks to all you fellows for your replies. It seems that I might need to add a 35S to my ever-growing collection. 22S, 28S, 33s, 48, 50... I'm holding out hope that the 50 keys will soften, but I'm not optimistic.

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