Ask HN: Should there be new RPN calculators to replace the TI-84?
I took an exam today where only TI calculators were available. I felt I was caught between some older models where the TI interface was not quite worked out.
And I don't see much progress then trying my daughter's TI-84.
Calculators, especially scientific and graphing calculators, are a niche product these days, almost exclusively limited to education and exam-taking. There is no impetus for changing the approved models, given the mountains of materials adapted to their use (TI actively worked with various educational bodies to promote the use of graphing calculators and helped prepare the curricula using their own.)
Don't expect great changes in this area, although the impending death of the Dept. of Education might shake up things. Not for the better, I think.
Education seems to be moving to computer based systems like GeoGebra and Desmos. So the market for separate calculators is becoming even more niche, mostly just die-hard fans who'll get stuff like SwissMicros devices
Back in college one summer, I had an HP calculator crammed full of programs I had written for various circuit and RF design courses I was taking. I didn't have any way to store them, other than writing them down on paper. On a whim that summer, I went to take the Ham Radio Extra class exam one weekend. The proctor said I needed to erase all the memory from my calculator before using it on the test. I told him no way was I going to do that, but suggested an alternative.
I had been curious how slide rules worked, and had found one after searching high and low for in half a dozen stores before finding probably the last one for sale in Atlanta. The slide rule was in my backpack, so I asked the proctor, could I used the slide rule instead? He chuckled, and said no problem. During the test, one of the proctors tapped me on the shoulder and asked me if he could bring me a bucket of water to cool down my "slip stick". I did pass the test that day, and I used to brag that I got my Extra Class license with a "Slide Rule endorsement".
I'm a for-funsies pilot and I took my most recent exam with a physical EB-6, which is a circular slide rule of sorts. Of course the way people take these exams these days is to just to memorize all the questions. The FAA hasn't seriously updated the question bank in years and there are known wrong answers in the answer key.
The only real place I've seen RPN calculators used post-2000 is in calculator competitions (oh yes they exist)
RPN is not a good fit for the classroom. It doesn't connect to the way math and arithmetic are taught, since ages. RPN comes from the days when parsing an expression in a calculator was hard. I've got a two RPN calculators at home, and I think it's cute, but it's a nerd thing.
If you want a non-TI calculator that's allowed in the classroom: look at the Casio and Numworks.
>Should there be new RPN calculators to replace the TI-84?
I'm not sure I really understand your question, TI-84 (and all other TI models) don't use RPN. You can run a program to allow RPN input you want, since most of the higher TIs are programmable. I believe some of HPs current lineup have a limited RPN mode available and SwissMicro makes some new RPN calculators.
>I took an exam today where only TI calculators were available.
That's common as they are the ones used to teach math classes and are vetted to prevent cheating on standardized tests.
>I felt I was caught between some older models where the TI interface was not quite worked out.
I have no idea what this is supposed to mean.
>And I don't see much progress then trying my daughter's TI-84.
Nor this.
Having been the proud owner of a TI-82 myself I can only surmise this guy has no idea what RPN means
Not what the OP asked for but related.
The link below is for a near perfect simulation of the classic HP-15C RPN calculator. Works on both desktop and mobile.
In a former lifetime, I was an engineer. I bought one of these in the early 1980s and used it for almost 40 years before the screen died. Very popular among my colleagues at the time.
https://jrpn.jovial.com/
If you want a native options on a mobile device, Free42 and 48sx work great on Android (I believe at least Free42 is on iOS). Emu48 works on desktop (personally I like `dc`). Look at SwissMicros if you want a physical calculator.
That is awesome. Thank you for posting this.
Need to find one of these for hp32SII
https://www.swissmicros.com/product/model-dm32
There are some RPN calculators from SwissMicros that are inspired by HP’s RPN calculators from the 1980s and 1990s:
https://www.swissmicros.com/products
There is also the HP-15c Collector’s Edition (I have one), which is still in stock: https://www.thecalculatorstore.com/c/hp15c
Two caveats:
1. These RPN calculators are not cheap.
2. Many standardized tests have lists of approved calculators, and it’s possible that the calculators I mentioned might not be on the list. TI has dominated the education market in the United States for the past few decades, and even during the heyday of HP’s RPN calculators, HP largely focused on engineers and other professionals rather than education. Thus, you may need to buy a TI calculator for exam purposes.
I love RPN calculators: I have a HP-48X that I bought used on eBay nearly 20 years ago when I was an undergrad, and my aforementioned HP-15c Collector’s Edition. However, these are collectibles for me; as a computer science professor I’m always in front of a computer, and thus I have access to the Unix dc command whenever I need an RPN calculator, and for more complex computations I have my choice of Excel and various programming languages.
Swiss Micros have some fairly decent recreations of HP's greatest hits. Pricey, but I am going to get myself one for my birthday. https://www.swissmicros.com/products
Inflation adjusted they are cheaper than the HP they are recreating. Even if you don't adjust for inflation they are competitive to the old HPs in the 1990s.
I have several of these and I'm really impressed with the quality. The DM32 is nice and has a manual available from SwissMicros, but I prefer the DM42n. I had a print shop print and spiral bind an HP-42 manual for me. Works good.
Have a look at https://www.numworks.com a easy to use scientific calculator that is opensource
As a high school student I can’t recommend the NumWorks enough (but you will absolutely find it lacking if you need it for anything other than high school maths).
It’s a really nice tool (although not an RPN calculator). It’s like if Apple designed a calculator… very intuitive.
That said, I wouldn’t call it fully open source. They had some issue because they released an update that locked down their calculators to satisfy school boards (because otherwise students could modify test modes to cheat on tests). The software on GitHub was also out of date, last time I checked.
I know they removed the CAS capabilities to appease school boards. Are you still able to replace the firmware with the CAS capable version?
Good to know, while I had purchased one for my daughter, I had only a cursory look at the released files.
Not really true anymore unfortunately: The latest models (post-2020?) are locked down and cannot use non-official FW.
I had to look it up:
RPN = reverse Polish notation
https://en.wikipedia.org/wiki/Reverse_Polish_notation
Wow. In my day it was well-known. HP calculator ads in magazines explained RPN and why it was better.
"Magazine? Had to look it up."
I did UIL competitions in Texas in the late 90s and early 2000s, including calculator competitions.
That's the only place I've ever heard of RPN, which is what nearly all of the winners used, and which we learned to stand a chance.
I waddled into my first UiL calculator test because the sponsor wanted to get more team members and spent most of my time blown away watching kids entering problems into two calculators simultaneously
When I was in high school in the 1980's, the other students knew RPN only as the reason they couldn't borrow my weird calculator.
IMHO we'd be better off focusing on policies that allow computers to be used on standardized exams. Hardly anybody uses a calculator in a real job, people at desks use computers, and even people who have to do calculations in a field environment use ruggedized tablets. Rather than working on revamping obsolete technology we should work on a way to make a computer acceptable to use on an exam in a way that addresses cheating concerns.
But if you really wanted to keep using a calculator, you should check out the HP Prime, Casio Prizm, or TI-Nspire series. The HP Prime has RPN, and all of these lines have color touch screens and a bunch of modern features. The TI-84 is not the pinnacle of technology, it is popular only because it is an exam-acceptable and an old standard format that people are used to.
As a Middle-Aged person who does math on the periphery of calculus reasonably often, for work and in my day to day life, my irritation with calculators is that their capabilities are largely driven by the education markets demands. The small handful of calculators with CAS abilities are usually kneecaped to what would be allowed in a testing environment.
I want a calculator that can do all the transforms for me and show the work so I know what I'm doing.
For my day-to-day needs I literally run a TI-89 emulator on my android phone these days. Seems silly.
[delayed]
I still have my old HP48GX, but I find I use iHP48 more often because it’s much faster. I had a 49G also but the keyboard died just from sitting in a drawer… the HP build quality took a nosedive in the late 90s.
I think there may be some confusion about "RPN" (Reverse Polish Notation). It was very popular with certain folks, Back In The Day, but I, personally, never warmed to it. I don't think it ever would have been mandated for tests. It was very much a "deep geek" notation.
But if you really want it, and are an Apple user, I have found that the PCalc app[0] has been excellent (I've used it for over 30 years). It works on multiple (Apple) platforms, and has RPN (the real RPN) built in, as a selectable option.
I suspect there's similar apps for Windows, Linux, and Android.
[0] https://pcalc.com
TI calculators are not RPN. I think HP made (makes?) RPN calculators.
Yeah, I'm also confused by this... the only RPN calculator I know of is the HP 15C, which is old school and not used in education.
I bought a HP50 (?) in uni to do symbolic math for some exam. It was RPN by default but you could switch.
> HP 15C, which is old school and not used in education.
Business courses frequently use it
You still see some HP12Cs on bank trading floors.
The HP Prime, though pricy, supports a decent RPN mode. Definitely for a higher level of education (CAS, programs, all that fun stuff), but approved for a decent amount of US based exams.
Pricy is relative. Looks like Amazon sells it for $125 (the SRP is $230)
As an engineering student in 1987, I bought a HP-28C. I recall it was the first calculator to do symbolic math
Original Price $235 which is close to what I paid. Adjusted for inflation $657
I think it was worth it.
Even 7th and 8th grades use TI Nspire CX calculators in my area.
As rightbyte said, RPN is an HP thing, so if you want an RPN calculator, ask for an HP. Most test administrators can help you.
>RPN is an HP thing
Not anymore, that's why older engineers pay inflated prices for old ones on ebay.
Or pay extra for https://www.swissmicros.com/products
Sadly my HP 48G is dead dead (water damage and corrosion) and they don't have a replacement for that.
So far my son (8th grade) really just uses Desmos https://www.desmos.com/calculator which is apparently also built-in to the SAT now (which is taken on a computer) - I have been trying to convince him a separate calculator is better but so far no luck.
The DB48X project looks interesting: https://48calc.org/
No. They're all ganked to be permitted on standardized tests anyway.
What is lacking from the TI-84? Why do you specifically want RPN?
Not sure I remember my TI-84 being RPN