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Do HP owners use Algebraic entry?
Message #1 Posted by designnut on 26 Oct 2007, 12:35 a.m.

I ask whether Algebraic entry is useful for HP owners. I also wonder if fractions are useful. Some conversions seem trivial, degrees C to F and cm to inches. Could these be eliminated? Sam

      
Re: Do HP owners use Algebraic entry?
Message #2 Posted by DaveJ on 26 Oct 2007, 1:06 a.m.,
in response to message #1 by designnut

Quote:
I ask whether Algebraic entry is useful for HP owners.

It is for me, in fact I prefer it over RPN (I can hear the gasps now...) I like having the choice.

Quote:
I also wonder if fractions are useful.

I only use them when entering a number. e.g. Sometimes I might use a formula that has fractions in it like Y=(2/5*X)/SQRT(2) So a fraction key helps occasionally.

But I can't recall ever needing fractions as a result though.

Quote:
Some conversions seem trivial, degrees C to F and cm to inches. Could these be eliminated? Sam

I like conversions, they are handy. But the ones included on most calcs are often useless for me. e.g. I need inches<>mm not inches<>cm

Dave.

            
Re: Do HP owners use Algebraic entry?
Message #3 Posted by bt_schmidt on 27 Oct 2007, 5:57 p.m.,
in response to message #2 by DaveJ

Quote:
I like conversions, they are handy. But the ones included on most calcs are often useless for me. e.g. I need inches<>mm not inches<>cm Dave.

umm, move the decimal point 1 place?

                  
Re: Do HP owners use Algebraic entry?
Message #4 Posted by DaveJ on 27 Oct 2007, 6:20 p.m.,
in response to message #3 by bt_schmidt

Quote:
umm, move the decimal point 1 place?

I expect my calculator to give me *exactly* what I want. So I shouldn't have to think about moving the decimal point one place. And it becomes even more ridiculous when you want to perform further operations on the number.

Dave.

                        
Re: Do HP owners use Algebraic entry?
Message #5 Posted by Garth Wilson on 27 Oct 2007, 8:08 p.m.,
in response to message #4 by DaveJ

Quote:
I expect my calculator to give me *exactly* what I want. So I shouldn't have to think about moving the decimal point one place.
That sounds dangerous. Hopefully you could tell if an input error put you off by a power of ten! When we used slide rules, the decimal place was usually kept in one's head. They were good for helping one's understanding of number relations. Students nowadays can get an answer way off and not realize it, thinking "the calculator is always right."
                              
Re: Do HP owners use Algebraic entry?
Message #6 Posted by DaveJ on 28 Oct 2007, 1:43 a.m.,
in response to message #5 by Garth Wilson

Quote:

That sounds dangerous. Hopefully you could tell if an input error put you off by a power of ten! When we used slide rules, the decimal place was usually kept in one's head. They were good for helping one's understanding of number relations. Students nowadays can get an answer way off and not realize it, thinking "the calculator is always right."


No I don't think the "calculator is always right". What I meant was that I want to use my calculator to give me the result I expect. I do not want it to be off by an order of magnitude and then have to correct it in my head or with extra keystrokes. To me, using an in<>cm conversion when I really want in<>mm is what is dangerous, and it's not elegant, so I won't use it. Instead I'll do it manually. My HP20S has in<>cm and I've never used it even though I do in<>mm conversions on a daily basis.

Dave.

      
Re: Do HP owners use Algebraic entry?
Message #7 Posted by Meenzer on 26 Oct 2007, 2:35 a.m.,
in response to message #1 by designnut

Quote:
I ask whether Algebraic entry is useful for HP owners.

I very seldomly switch my HPs to algebraic mode. In case I want algebraic entry I grab a Casio.
Quote:
I also wonder if fractions are useful.

Very useful for me when checking my kids' homework. But again, I mostly grab a Casio with much more convenient fractions input.
Quote:
Some conversions seem trivial, degrees C to F and cm to inches. Could these be eliminated? Sam

Living and working in Europe, I have no use at all for metric/US conversions. I don't need dedicated keys for units conversions. If it was in some menu to use it at times I would be glad. I could even live without that. Had I really to do some conversions, I would look it up in my "Mythbuster's Thomas J. Glover Pocket Ref" (!, Har Har!!) and easily write a short program and purge it afterwards ;-)

Edited: 26 Oct 2007, 7:07 a.m. after one or more responses were posted

            
Re: Do HP owners use Algebraic entry?
Message #8 Posted by Lyuka on 26 Oct 2007, 6:53 a.m.,
in response to message #7 by Meenzer

I'd like to have HP->kW conversion instead of lb->kg conversion, and wish if these conversion keys were user definable.

                  
Re: Do HP owners use Algebraic entry?
Message #9 Posted by Craig Webster on 26 Oct 2007, 10:30 a.m.,
in response to message #8 by Lyuka

Quote:

if these conversion keys were user definable.


For the conversion issue, I think you've hit the nail on the head. being able to define them would be useful. I could have barrels to litres and MPa to psi, oh and lb-ft to N-m.

As for the algebraic mode, it's useful if one of the spasm's of organic matter sitting next to me need to use my calculator.

      
Re: Do HP owners use Algebraic entry?
Message #10 Posted by Mark Storkamp on 26 Oct 2007, 10:58 a.m.,
in response to message #1 by designnut

Quote:
I ask whether Algebraic entry is useful for HP owners
I never use algebraic entry. Only RPN.
Quote:
I also wonder if fractions are useful
I often use my 35s set to display in 64ths, or factors of 64 (32, 16, 8, &c).
Quote:
Some conversions seem trivial, degrees C to F and cm to inches. Could these be eliminated?
Absolutely. Every day I'm converting from inch to mm and back, but I don't need a dedicated key for it (and I never use the inch to cm key the 35s has since it's more trouble to try to remember whether to multiply or divide by 10 depending upon which way I'm converting). I have no use whatsoever for the other metric/imperial conversions. I would much rather have had polar/rect or hms+ and hms-, or even just an A &/| B key that would begin executing programs A & B (maybe the shifts for A could execute C & D)
      
Re: Do HP owners use Algebraic entry?
Message #11 Posted by bill platt on 26 Oct 2007, 12:33 p.m.,
in response to message #1 by designnut

Once I discovered Algebraic methods on HP, I became a pretty enthusiastic user. Even with the unary minus confusion of the 32sii, I very quickly found that I could use equations for a huge amount of stuff that I used to program in RPN.

Similarly, when opened my eyes to the other models (17bii, 48GX, 27s) I became a strong supporter of the algebraic solvers and algebraic objects.

Back in the early 90s, if only I'd bothered to look at the Algebraic 27s, I might have left RPN behind forever.

And the 48GX (and 49 and 50) is totally cool with the ability to use agebraics and stack-based manipulation together. The holy grail.

(BTW I am the quintessential HP profile customer: 1st in my school with one, used hp exclusively for over two decades, looked only for hp and rpn when I lost my 11c way back when...preferred (and used!) a slide rule rather than a Ti when I had a repair being made!)

Fractions: I was an instant enthusiastic user of fraction input (but not display) on the 32sii. It goes with the territory (U.S. engineering).

Similarly, I found the unit conversions useful. They save keystrokes which is the whole point. On the 11c, they were printed on the back, which I also think is good.

Edited: 26 Oct 2007, 12:35 p.m.

      
Re: Do HP owners use Algebraic entry?
Message #12 Posted by Martin Pinckney on 26 Oct 2007, 4:11 p.m.,
in response to message #1 by designnut

Quote:
I ask whether Algebraic entry is useful for HP owners. I also wonder if fractions are useful. Some conversions seem trivial, degrees C to F and cm to inches. Could these be eliminated? Sam

I use algebraic entry for most calculations. Started on TI, only switched to HP after: a) multiple TI's keyboards and displays went awry, and b) HP started making algebraic Pioneers. I do often switch to RPN for unary functions (that's the way the older TI's and most HP Pioneers work), and units conversions.

I do use fractions a lot. That's one reason I bought the 35s.

I like conversions, but I agree with the sentiment that it seems that the ones provided are not the ones you need. I, too wish that HP would make the units conversions customizeable, and in fact I suggested that to HP recently.

      
Re: Do HP owners use Algebraic entry?
Message #13 Posted by Jim Creybohm on 26 Oct 2007, 4:55 p.m.,
in response to message #1 by designnut

Unit conversions are useful, but not in->mm etc., but rather like the 41 or 48's unit conversions. I need stuff like btu/hour -> J/sec.

As for Algebraic, because I have been using a 20s, I have become more familiar with the AOS method. Now that the 35 is back, I am slowly getting more accustomed to thinking in RPN.

Lastly although not related, the 35 is for me, a programmers calculator. It is not yet my engineering programming calculator of choice. I would like to have greater control over textual input before it becomes my "main play".

      
Re: Do HP owners use Algebraic entry?
Message #14 Posted by Garth Wilson on 27 Oct 2007, 1:06 a.m.,
in response to message #1 by designnut

My HP-71 has algebraic entry, and even the CALC mode which was supposed to be so great, but I don't like that part of it. The 71 is an outstanding little computer, vastly underestimated and scorned by HP's own marketing department; but for a calculator, I usually reach for my 41cx. I have the tiny programs for converting between mm and inches and between C and F assigned to keys. No other conversions. Fractions are just unfinished division problems that I have no use for as calculation results in my circuit design work.

      
Re: Do HP owners use Algebraic entry?
Message #15 Posted by Ed Look on 27 Oct 2007, 1:38 a.m.,
in response to message #1 by designnut

Well, I don't.

I am so used to and prefer using RPN that I really never even touch the HP-20S (an algebraic only machine) my wife got me a long time ago, even if it's beautiful to look at. I continued to use my HP-34C until I couldn't take it anymore (the display began to get rather erratic) and replaced it with the RPN 32SII.

I've never used equation entry, either. I program in any repetitive or lengthier calculation I need with the RPN keystroke programming. I have also a rather nice old Casio, the fx-4200p, now for quite a few years. It too, is very prettily designed, slim, lightweight, with a very nice dot matrix LCD display. But it's algebraic and only has formula memory, not keystroke program memory... and I have very rarely used it.

It's hard for me to imagine how anyone, once smitten by RPN (though I admit when I first encountered it, I resisted it, but was drawn in by the power and quality and solidity of the HP product) can go back and use algebraic entry. (Ask a Met fan if he cares about what's going on with Joe Torre; it's much the same thing, I guess.)

            
Re: Do HP owners use Algebraic entry?
Message #16 Posted by Meenzer on 27 Oct 2007, 1:42 a.m.,
in response to message #15 by Ed Look

Quote:
... my wife got me a long time ago, even if it's beautiful to look at.

Congratulations for having a beautiful wife ;-)

                  
Re: Do HP owners use Algebraic entry?
Message #17 Posted by Ed Look on 27 Oct 2007, 1:49 a.m.,
in response to message #16 by Meenzer

Why, thank you! Oh, and my HP-20S and Casio fx-4200p thank you too.

                        
Re: Do HP owners use Algebraic entry?
Message #18 Posted by Meenzer on 27 Oct 2007, 2:14 a.m.,
in response to message #17 by Ed Look

;-)

                  
Re: Do HP owners use Algebraic entry?
Message #19 Posted by DaveJ on 27 Oct 2007, 3:52 a.m.,
in response to message #16 by Meenzer

Quote:
Congratulations for having a beautiful wife ;-)

My wife is WONDERful and lets me me play with my electronic gizmo's. But she has her own tech toys too!

Dave.

            
It's a religious issue!
Message #20 Posted by Palmer O. Hanson, Jr. on 27 Oct 2007, 3:57 a.m.,
in response to message #15 by Ed Look

Quote:
It's hard for me to imagine how anyone, once smitten by RPN (though I admit when I first encountered it, I resisted it, but was drawn in by the power and quality and solidity of the HP product) can go back and use algebraic entry. (Ask a Met fan if he cares about what's going on with Joe Torre; it's much the same thing, I guess.)

Just like Mets fans and Yankee fans the HP/RPN and TI/AOS/EOS communities are not only different but, more importantly, are each insular and provincial. That isn't just my idea. When Wozniak wrote of finding that the famous (or maybe infamous) Mach number equation was easily solved with one of TI's early scientific machines he reported that "... My colleagues couldn't believe it. I told them that you just copy the formula from left to right but not one of them could see through their postfix fog. ... ... None of them could do what I had done, forget that they have to be smart." It isn't just the HP/RPN community that is like that. The TI/AOS/EOS community is just as provincial. They "know" that RPN doesn't really stand for Reverse Polish Notation but rather for Really Pathetic Notation. Why would anyone want to evaluate an equation other than by simply entering it as one sees it on paper?

In a sense the RPN vs AOS debate has always been more of a religious issue than a technical issue. The problem with religions is that they can become cult-like and corrupt. A book on that subject When Religion Becomes Evil by Charles Kimball lists warning signs of corruption in religion where two of the signs are "Absolute Truth Claims" and "Blind Obedience." Doesn't that sound like the long standing RPN vs AOS debate

                  
Re: It's a religious issue!
Message #21 Posted by Meenzer on 27 Oct 2007, 4:10 a.m.,
in response to message #20 by Palmer O. Hanson, Jr.

Quote:
In a sense the RPN vs AOS debate has always been more of a religious issue than a technical issue.

For some things I use a HP and my brain.
For some things I use a Casio and my brain.
For some things I use a TI and my brain.
For some things I use a Sharp and my brain.
For some things I use a Win-PC and my brain.
For some things I use a Linux-Box and my brain.
For some things I use ... damn, I don't own a MAC
For some things I use only my brain.

Do you think this may be related to me being an atheist? ;-)

                        
Re: It's a religious issue!
Message #22 Posted by Palmer O. Hanson, Jr. on 27 Oct 2007, 10:23 a.m.,
in response to message #21 by Meenzer

Quote:
For some things I use a HP and my brain.
For some things I use a Casio and my brain.
For some things I use a TI and my brain.
For some things I use a Sharp and my brain.
For some things I use a Win-PC and my brain.
For some things I use a Linux-Box and my brain.
For some things I use ... damn, I don't own a MAC
For some things I use only my brain.

Do you think this may be related to me being an atheist? ;-)

Richard Vanderburg who was the editor/publisher of 52 Notes and Maurice Swinnen who was the first editor/publisher of TI PPC Notes used the term "bilingual" for those rare individuals who were competent and comfortable using both RPN and AOS. I suspect that they would have described you as "multilingual".

                  
Re: It's a religious issue!
Message #23 Posted by Valentin Albillo on 27 Oct 2007, 11:15 a.m.,
in response to message #20 by Palmer O. Hanson, Jr.

Hi, Palmer:

    Palmer wrote:

      "They "know" that RPN doesn't really stand for Reverse Polish Notation but rather for Really Pathetic Notation."

        I'd say "Ridiculously Prehistoric Notation" :-)

      "Why would anyone want to evaluate an equation other than by simply entering it as one sees it on paper? "

        It might be useful if you need to see or check intermediate results, else it makes no sense.

      "The problem with religions is that they can become cult-like and corrupt. A book on that subject When Religion Becomes Evil by Charles Kimball lists warning signs of corruption in religion where two of the signs are "Absolute Truth Claims" and "Blind Obedience"".

        Freedom of speech in the United States is protected by the First Amendment to the United States Constitution, assuming you live in the US, but if I were you I would refrain from unnecessarily bringing in off-topic religious issues in this forum, even if in good humor or for fun. You can easily offend someone else's sensibilities and in any case experience shows that it has the potential to be a thorny issue. Caveat emptor.

    As for me, now I never use RPN in real life. If I'm at some computer, I use Emu71 to perform all kinds of simple and complex numeric computations with utmost speed and ease. If I'm in the field, I use a vintage SHARP handheld which is as small as an HP-15C, provides BASIC programming and algebraic evaluation, and is much faster and convenient.

    For playing a little, having a fond remembrance of the good old days, concocting challenges, and writing articles, I resort to RPN frequently. But apart from that, I never use it, and now that the new HP 35s does include convenient, editable, arbitrary-length equations which can be seamlessly embedded in RPN programs making them much shorter and easier to write, and which can be integrated and solved for any variable, I expect to see power users slowly getting accustomed and migrating to a mixed paradigm and ultimately to a modern, essentially algebraic one.

Best regards from V.
                        
Re: It's a religious issue!
Message #24 Posted by Palmer O. Hanson, Jr. on 27 Oct 2007, 10:45 p.m.,
in response to message #23 by Valentin Albillo

I wrote:

Quote:
They "know" that RPN doesn't really stand for Reverse Polish Notation but rather for Really Pathetic Notation
You wrote:
Quote:
I'd say "Ridiculously Prehistoric Notation"
In fairness I should note that Richard Nelson prefers Really Productive Notation.

I wrote:

Quote:
Why would anyone want to evaluate an equation other than by simply entering it as one sees it on paper?
You wrote:
Quote:
It might be useful if you need to see or check intermediate results, else it makes no sense.
With A.O.S. it was possible to see most of the intermediate results. That's not so with E.O.S. But with E.O.S. the user sees the entire equation as it is entered and typically has the playback option.

I apologize if I offended you or anyone else by characterizing the RPN/AOS debate as a religious issue. But, the facts are that many of the statements of the adherents of each side exhibit many the characteristics of the phenomenon known in the USA as a religious cult.

                  
Re: It's a religious issue!
Message #25 Posted by Garth Wilson on 27 Oct 2007, 1:47 p.m.,
in response to message #20 by Palmer O. Hanson, Jr.

Quote:
Why would anyone want to evaluate an equation other than by simply entering it as one sees it on paper?
Because in real life, the equation is seldom on paper first. At each step, I'm thinking about what to do to the numbers next. When I do come up with an equation and write it down, I follow the same procedure, and often end up forming it from the inside out, sometimes meaning I didn't leave myself enough blank paper on the left or the top to "grow" the equation to completion. In my programming, I quit looking for new languages when I met Forth. It was great to finally get rid of the piles of parentheses.

Edited: 27 Oct 2007, 1:48 p.m.

                  
Re: It's a religious issue!
Message #26 Posted by Ed Look on 27 Oct 2007, 5:39 p.m.,
in response to message #20 by Palmer O. Hanson, Jr.

Okay, okay- I'll admit that I love RPN because of its power in the earlier days of calculators. But it's still a generally very efficient entry method and even programming method in these small, handheld... well, if a PC or a Mac is a microcomputer, I guess calcs are semimicrocomputers (I suspect we won't have nanoscale circuits commercially in the forseeable future... and little nanoparticles or nanowires don't yet count, as they are still lab toys).

Anyway, for a machine so small, which constrains still to this day its power, for you can't have a monitor sized screen and a Selectric sized keyboard and an external flash hard drive (or you'd have a laptop, and it suddenly is less useful for what we want calcs for- lightness and compactness), and despite the gigantic leaps we have made in the sizes of calculator memories, a way to save keystrokes in programming (or even just "off the [key]board calculating".

Besides, I just LOOOOVE not having to press an "=" key.

And, Palmer, I'm a city boy, but as someone once told me, and I totally agree, sometimes big city boys are the most provincial because of their smugness. This afflicts even or especially the very educated, like HP RPN users.

                        
Re: It's a religious issue!
Message #27 Posted by Palmer O. Hanson, Jr. on 28 Oct 2007, 3:59 a.m.,
in response to message #26 by Ed Look

Quote:
And, Palmer, I'm a city boy, but as someone once told me, and I totally agree, sometimes big city boys are the most provincial because of their smugness. This afflicts even or especially the very educated, like HP RPN users.

That comment takes me back to my boot camp days in 1951. About half of our company was from Brooklyn. The other half, my half if you will, was from small towns in Minnesota and Wisconsin. The Brooklynites could't believe that we couldn't name the five boroughs of NYC. We couldn't believe that some of them had never been beyond NYC and Long Island. They thought that we lived "way out west". We said that "way out west" to them meant the other side of the Hudson River. The amazing thing is that the company commander managed to get us to work together.

                              
Re: It's a religious issue!
Message #28 Posted by Don Shepherd on 28 Oct 2007, 11:06 a.m.,
in response to message #27 by Palmer O. Hanson, Jr.

Palmer, that reminds me of the movie "Sergeant York". He was a country boy from Tennessee who was in a World War I unit with a fellow from the Bronx, as I recall. That fellow described the subway as a "train that runs under the ground." Poor Sgt. York could not fathom that. A great movie (now on DVD) about a real American hero.

                              
Re: It's a religious issue!
Message #29 Posted by Ren on 7 Nov 2007, 11:48 a.m.,
in response to message #27 by Palmer O. Hanson, Jr.

Quote:

That comment takes me back to my boot camp days in 1951. About half of our company was from Brooklyn. The other half, my half if you will, was from small towns in Minnesota and Wisconsin. The Brooklynites could't believe that we couldn't name the five boroughs of NYC. We couldn't believe that some of them had never been beyond NYC and Long Island. They thought that we lived "way out west". We said that "way out west" to them meant the other side of the Hudson River. The amazing thing is that the company commander managed to get us to work together.


This bonding of humanity has been called "human cement" by an author/speaker. It grows out of the circumstances of Basic Training /Boot Camp. Young men(?) are thrown together, separated from their family/friends support group, they are "torn down" and "built back up" through the intensity of the training. And working together to get through the situation they learn to trust and respect each other as they learn about their own and others weaknesses and strengths. At the completion of BT, the "us/them" paradigm has been replaced by "we".

And because the intensity of USMC Basic is greater than the average sailor/soldier/airman, their bond is stronger throughout life. ("Once a Marine, always a Marine")

Ren

dona nobis pacem

                  
Re: It's a religious issue!
Message #30 Posted by Ken Shaw on 6 Nov 2007, 11:51 a.m.,
in response to message #20 by Palmer O. Hanson, Jr.

Quote:
Why would anyone want to evaluate an equation other than by simply entering it as one sees it on paper?

My reason is that I most often use a calculator when I am exploring a problem that hasn't been formulated on paper. RPN just seems more efficient to use because you can easily undo steps and recover previous work without re-entering the numbers. I went through a physics education using a Radio Shack-badged TI, and didn't encounter RPN until the working world (HP12C), but once I'd adapted, I never wanted to go back.

      
Re: Do HP owners use Algebraic entry?
Message #31 Posted by Maximilian Hohmann on 27 Oct 2007, 5:21 a.m.,
in response to message #1 by designnut

Good morning,

Quote:
I ask whether Algebraic entry is useful for HP owners.

For me, it is as useful (or useless, see the thread about economist vs. engineer) as RPN. I owe a lot to AOS because Ti calculators helped me through school and university (HPs were prohibitively expensive then). Probably, I am not a "true RPN" user anyway because I never press keys like Roll-Up Roll-Down or x<>y :-) But I wouldn't go so far as to switch an HP calculator to algebraic mode.

Quote:
I also wonder if fractions are useful.

Fractions are completely unheard-of in my part of the world. You learn it a school long before you are allowed to use a calculator, and thereafter you never ever encounter them again. Our metric world is "decimal places only".

Quote:
Some conversions seem trivial, degrees C to F and cm to inches. Could these be eliminated?

As far as I am concerned: Yes, get rid of trivial conversions. I need a lot of conversions in one of my jobs (aviation), but they are much more complicated. User-defineable conversions would be greatly appreciated!

Greetings, Max

Edited: 27 Oct 2007, 5:23 a.m.

            
Re: Do HP owners use Algebraic entry?
Message #32 Posted by DaveJ on 27 Oct 2007, 6:48 a.m.,
in response to message #31 by Maximilian Hohmann

Quote:
Probably, I am not a "true RPN" user anyway because I never press keys like Roll-Up Roll-Down or x<>y :-)

I use X-Y excessively on both RPN and algebraic calcs, more so on the algebraic calcs I think. Seems like almost every calculation I do needs the X-Y key. I seem to have little use for ROLL while using RPN though.

Dave.

                  
Re: Do HP owners use Algebraic entry?
Message #33 Posted by Arne Halvorsen (Norway) on 27 Oct 2007, 10:44 a.m.,
in response to message #32 by DaveJ

Hehe, I love the x<>y when in user mode, propably for the wrong reason!: When happen to entered the numbers in wrong sequence when to use operations where operand order matters :-) Thats HP for you, looking out for the not to sober engineer!

                  
"Roll down" and "roll up"
Message #34 Posted by Karl Schneider on 27 Oct 2007, 1:59 p.m.,
in response to message #32 by DaveJ

Hi, Dave --

Quote:
I seem to have little use for ROLL while using RPN though.

One stack-roll function must be provided to give the user convenient and complete stack control and viewing of contents. "Roll down" is more appropriate for that purpose.

VIEW and direct storage/retrieval of stack registers can also fulfill those purposes, but those functions are not available on all models.

"Roll up" is mainly a convenience for programming -- tidier than three roll-downs -- and is useful for checking the stack-t register without the VIEW function. It's noteworthy that the HP-32S doesn't have "roll up" at all; it is not on the keyboard on the HP-41 and HP-42S.

-- KS

                        
Re: "Roll down" and "roll up"
Message #35 Posted by Ed Look on 27 Oct 2007, 5:20 p.m.,
in response to message #34 by Karl Schneider

Yes I agree, Karl- the rolling functions are rather useful in programming. It helps to save STO and subsequent RCL steps.

                        
Re: "Roll down" and "roll up"
Message #36 Posted by Trent Moseley on 27 Oct 2007, 10:50 p.m.,
in response to message #34 by Karl Schneider

Karl,

I agree on the availability of the "roll up" feature being used mostly in programing. But having it buried on the 42S in a menu was a mistake.

I learned RPN programing on my 25C, three "roll downs" took up a lot of program lines when there were only 49 available.

tm

                              
Access of HP-42S functions
Message #37 Posted by Karl Schneider on 28 Oct 2007, 3:04 p.m.,
in response to message #36 by Trent Moseley

Hi, Trent --

Quote:
.. having ("roll up") buried on the 42S in a menu was a mistake.

Ah, but "roll up" -- and a number of other useful functions on the HP-42S -- aren't even included within menus. They must be accessed through the function catalog or be spelled out, HP-41 style. Other functions might be accessed repeatedly in succession, making them tedious to execute through their menus. It's helpful to assign these functions to positions in the user's three-level CUSTOM menu.

Other examples: %CH, CLV, VIEW, and the six hyperbolic functions (which do have their own menu on the HP-27S).

Each HP-42S function with its assigned key and menu (if any) is listed in the orange-tabbed Operation Index of the Owner's Manual, pp. 310-335.

-- KS

                              
Re: "Roll down" and "roll up"
Message #38 Posted by Vieira, Luiz C. (Brazil) on 28 Oct 2007, 11:47 p.m.,
in response to message #36 by Trent Moseley

Quote:
But having it buried (the "roll up" feature) on the 42S in a menu was a mistake.
In the HP41 it must be spelled out or assigned to a key, as you may know.
Quote:
(...)three "roll downs" took up a lot of program lines when there were only 49 available.
Also, the HP12C (and the newer versions) does not have it, neither the other financial models with RPN features. Indeed, 'roll-up' has its better usage in programs. Keepping track of Y-register contents demands some practice. T-register contents sometimes can only be kown after some full-stack tracking.

Cheers.

Luiz (Brazil)

      
Re: Do HP owners use Algebraic entry?
Message #39 Posted by Walter B on 27 Oct 2007, 11:47 a.m.,
in response to message #1 by designnut

Algebraic entry: For me, though started with a TI SR50 far ago, RPN formed my way of thinking calculations. For number crunching or even easier stuff, I'm lost with an algebraic calc. Always tend to type postfix and lose the results. Equation mode may be a different story -- I didn't use it so far but expect it to be easy, thus helpful.

Fractions: I don't need them. The decimal equivalents of the most common fractions I know by heart. And everyone knows half a cm are 5mm, and a quarter of a km are 250m.

Conversions: Not needed at all. Easy to program if they should become necessary. See other thread and posts above.

Edited to correct a typo

Edited: 28 Oct 2007, 10:13 p.m.


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