HP35’s x^y Why?

10302021, 06:33 PM
Post: #1




HP35’s x^y Why?
Hi all.
Yeah, all it takes is an x<>y press before the x^y key. So what was the reasoning for the 35’s x^y instead? Thanks 

10302021, 06:43 PM
Post: #2




RE: HP35’s x^y Why?
(10302021 06:33 PM)Matt Agajanian Wrote: Hi all. Reverse Polish Notation maybe? To do 4^3 3 <enter> 4 x^y Tom L Cui bono? 

10302021, 07:41 PM
Post: #3




RE: HP35’s x^y Why?
Perhaps:
1. It was first on the history of handhelds. Later on the 45, perhaps HP felt that entering the base first was more 'natural'. 2. Perhaps it inherited it from the 9100 where the X Register Display was physically below the Y Register Display  thus the Y visually is above the X. TomC (10302021 06:33 PM)Matt Agajanian Wrote: Hi all. 

10302021, 08:46 PM
(This post was last modified: 10302021 08:55 PM by Peet.)
Post: #4




RE: HP35’s x^y Why?
I also suspect HP first chose the "logical" way with x^y (like x^2) but then noticed that y^x (like 10^x) feeled more natural to the user similar to simple arithmetic (like y enter x *).
Most curious is probably the Prime with an x^y key that does y^x My calculators  former: CBM PR100, HP41CV, HP11C, HP28S  current: HP48G, HP35S, Prime, DM41X, DM42, HP12C 

10302021, 09:54 PM
Post: #5




RE: HP35’s x^y Why?  
10302021, 11:43 PM
(This post was last modified: 10312021 01:37 AM by Steve Simpkin.)
Post: #6




RE: HP35’s x^y Why?
(10302021 09:54 PM)Gerson W. Barbosa Wrote:(10302021 08:46 PM)Peet Wrote: Most curious is probably the Prime with an x^y key that does y^x Well the Prime is, first and foremost, an *algebraic* graphing calculator. X^Y is not an unusual label for the power key on traditional algebraic calculators. It functions as a Y^X key in RPN mode. Most modern algebraic models use the ^ key for powers now. **Edited to fix the typo "Y^Y", It is now corrected to "Y^X". 

10312021, 12:00 AM
Post: #7




RE: HP35’s x^y Why?
I believe you mean that the key functions as an “x”^”y” key in RPN entry mode choice. In algebraic mode, in the text book mode, it is quite clear how the key works as hitting “x”, then x^y produces a curser space top right of “x’ for the “y” power to be keyed in.


10312021, 12:23 AM
Post: #8




RE: HP35’s x^y Why?
(10312021 12:00 AM)lrdheat Wrote: I believe you mean that the key functions as an “x”^”y” key in RPN entry mode choice. In algebraic mode, in the text book mode, it is quite clear how the key works as hitting “x”, then x^y produces a curser space top right of “x’ for the “y” power to be keyed in. I think I had it correct. When the Prime is in RPN mode, the key labeled “X^Y” appears to function as a Y^X key just like the traditional HP RPN and RPL models (other than the HP35). For example: 5 Enter 2 X^Y produces 25 as would be expected by RPN/RPL users. 

10312021, 01:09 AM
Post: #9




RE: HP35’s x^y Why?
(10312021 12:23 AM)Steve Simpkin Wrote:(10312021 12:00 AM)lrdheat Wrote: I believe you mean that the key functions as an “x”^”y” key in RPN entry mode choice. In algebraic mode, in the text book mode, it is quite clear how the key works as hitting “x”, then x^y produces a curser space top right of “x’ for the “y” power to be keyed in. FYI  I think you're right, but in fact you did write it wrong just above where it says " It functions as a Y^Y key in RPN mode." Bob Prosperi 

10312021, 01:34 AM
Post: #10




RE: HP35’s x^y Why?
(10312021 01:09 AM)rprosperi Wrote:(10312021 12:23 AM)Steve Simpkin Wrote: I think I had it correct. When the Prime is in RPN mode, the key labeled “X^Y” appears to function as a Y^X key just like the traditional HP RPN and RPL models (other than the HP35). For example: 5 Enter 2 X^Y produces 25 as would be expected by RPN/RPL users. Oops. I completely missed what lrdheat was trying to tell me. Sorry about that. I will edit my post to fix that typo. Thanks to both of you for spotting that. 

10312021, 07:45 AM
(This post was last modified: 10312021 11:47 AM by Peet.)
Post: #11




RE: HP35’s x^y Why?
(10302021 11:43 PM)Steve Simpkin Wrote: Well the Prime is, first and foremost, an *algebraic* graphing calculator. X^Y is not an unusual label for the power key on traditional algebraic calculators. e.g. TI59, TI30, HP22S or HP17B also had y^x because even on this algebraic calculators you type the base first and than the exponent. The HP35 way (exponent enter base > x^y) was strange but the 35 was the first of its kind and HP didn't know any better at the time. The label on the Prime and a key what makes the opposite (Numworks shares this incoherent behavior) is very weird. My calculators  former: CBM PR100, HP41CV, HP11C, HP28S  current: HP48G, HP35S, Prime, DM41X, DM42, HP12C 

10312021, 01:31 PM
Post: #12




RE: HP35’s x^y Why?
As weird as x^y seems, it does make it easier to compute "power towers", e.g. 1.02^1.03^1.04^1.05^1.06 or similar. You actually start at the right side, so 1.05^1.06 first. 1.06 ENTER 1.05 x^y 1.04 x^y 1.03 x^y 1.02 x^y.


10312021, 07:07 PM
Post: #13




RE: HP35’s x^y Why?
(10312021 07:45 AM)Peet Wrote:(10302021 11:43 PM)Steve Simpkin Wrote: Well the Prime is, first and foremost, an *algebraic* graphing calculator. X^Y is not an unusual label for the power key on traditional algebraic calculators. Yes, I spoke too soon. While many early Casio scientific calculator models had X^Y keys, almost every other manufacturer had Y^X keys. No mater how they were labeled, they always worked the same way on algebraic models. 

10312021, 08:18 PM
Post: #14




RE: HP35’s x^y Why?
Interesting, I don't think I've ever seen the predefined function X^(1/Y) before, nevermind have it right on the keyboard. Thx for sharing the photo.
Bob Prosperi 

10312021, 08:26 PM
Post: #15




RE: HP35’s x^y Why?  
10312021, 09:18 PM
Post: #16




RE: HP35’s x^y Why?
(10312021 07:07 PM)Steve Simpkin Wrote: No mater how they were labeled, they always worked the same way on algebraic models. Algebraic calculator in the 70s and 80s were already illogical but I wouldn't expect that from a modern calculator like the Prime. It's better if the keys are labeled properly and not confused. My calculators  former: CBM PR100, HP41CV, HP11C, HP28S  current: HP48G, HP35S, Prime, DM41X, DM42, HP12C 

10312021, 09:39 PM
(This post was last modified: 10312021 10:20 PM by Steve Simpkin.)
Post: #17




RE: HP35’s x^y Why?  
10312021, 09:49 PM
Post: #18




RE: HP35’s x^y Why?  
10312021, 11:59 PM
Post: #19




RE: HP35’s x^y Why?
(10312021 09:39 PM)Steve Simpkin Wrote:(10312021 08:18 PM)rprosperi Wrote: Interesting, I don't think I've ever seen the predefined function X^(1/Y) before, nevermind have it right on the keyboard. Thx for sharing the photo. So, it seems to be a Casiounique thing I guess? While the math of the operation is obviously of use for a variety of things, it seems an odd choice to allocate and commit to a permanently assigned key. Didn't seem to catch on though... Odd. Bob Prosperi 

11012021, 12:51 AM
Post: #20




RE: HP35’s x^y Why?
(10312021 11:59 PM)rprosperi Wrote:(10312021 09:39 PM)Steve Simpkin Wrote: No problem, Bob Here are some other Casio models that had that key as well. Very odd. I just noticed Casio is still including this function along with X^Y on at least one of their current models… 

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