I'm one of the last people at my workplace to use a calculator. I'm a scientist, not an engineer, so I use a scientific calculator. ;-)

The schools ruined calculators.

I still find a calculator handy, even when I've already got Python going on my PC. It's easier to use the calculator with one hand, especially in the workshop. You can get a Casio solar at Target for 10 bucks.

My wife really prefers RPN, so I gave her my last HP when hers died.

> The HP50g that came much later is better in every respect

Absolutely not. The big fail on everything after the 48SX was the keyboard.

I could sit in an exam and punch buttons without even looking at the calculator. I could feel the positive "click" from every single keypress, and I don't remember my 48SX ever dropping a keypress for any basic operation.

By contrast, the 49/50 series had mushy keyboards that bounced or failed to register presses. I still have 3 48SX calculators that I can use--I sold all my 49/50 series.

The excellent keyboard is bar none the big feature that I can't duplicate with any modern calculator.

I really wish some mechanical engineer would do a teardown on the old HP calulators and analyze why the keyboards were so damn good.

> I admire the project, although I would probably have taken a different path (emulation) to get the biggest effect with the smallest possible effort :-)

Emulators are stuck in the past, since they need to rely on the HP ROMs. So all the nice new features in DB48x, like variable-precision decimal arithmetic, support for higher-resolution graphics and colour, tail-recursion optimization, object size optimizations, polar and rectangular complex numbers or vectors, or the extensive Markdown-based builtin help would all be impossible to implement.

> I wish there was a good HP50G emulator for iOS — there used to be one, but it was abandoned (contact me if you want to develop it and would like to get the source code, it was under the GPL and I got it from the author).

I have two pretty good emulators on my iPhone, one is iHP48, the other is i48. Both can emulate the HP50G if you load the correct ROM, IIRC.

That being said, I second the idea that if you got the source in GPL form, you should publish them on GitHub. Or share with me and I will do it, possibly restore it (I have vague plans to restore Emu71 as well, when I'm done with DB48x).

> No, this is not replaced by typing "python" (or "bc", or anything else, really) at your command prompt.

Why not? At least I can easily copy the results and the code to a document which avoids transcription errors. Or do you mean that there simply isn't a program that has the functions you use?

I never liked the 48 series or the 50G (I own both) that much. I can never remember how to use them half of the time. I always end up back with my 38 year old HP 15c. That has done me through separate engineering and mathematics degrees and about 30 years worth of jobs.

They just issued new ones as well! (HP 15CE)

TBH TI-89 titanium is a better engineering calculator since the UI is way better. I have both a HP50G and a TI-89 titanium and I've done way more useful engineering work on the TI-89 titanium just because it's so much easier and accessible. Also of course, BASIC is a lot easier than reverse polish lisp for making some quick scripts.

Also I will add, there are known symbolic math issues on the HP50G due to the CAS system it uses. I will see if I can find a link.

> No, this is not replaced by typing "python" (or "bc", or anything else, really) at your command prompt.

Why?

I loved my HP 48G when I was in school (even if it was much slower than the Ti 81 it replaced when it came to graphing). I regret throwing it away because of the nostalgia, but I don't feel a need for using it these days.

As such I am genuinely curious about what rewards you get from using an engineering calculator in your work. That's an honest question: I would really like to have an excuse to get my hands on a 48G again!

Thank you for putting in a good word for "real" calculators. My HP-15c is always within reach.

Solid list of basic gym equipment as well. I'd add a good dumbbell set to your list unless you lumped those under "weights". A few different types of bars, a dip belt for adding weight to dips and pullups, and a low / mid / high cable set with various handles are also nice to have. Bonus points for a reverse hyper.

The HP 48GX got me through from high school college prep to EE/CS. I also happen to own an HP 48 overhead projector display and a thermal printer. Now, I just need an overhead projector to even use (the former). Sharing software was the killer app of the HP 48 G series, and the app that turned the serial IR port into a universal learning remote was a pranksters' dream because the IR LED was so overpowered.

>Incidentally, many young people (yes, I know how that sounds) do not know how useful a good engineering calculator can be and do not want to learn how to use one. They are missing out. Yes, there is a steep learning curve, but the rewards are significant if you do any amount of calculation in your hobby or work. No, this is not replaced by typing "python" (or "bc", or anything else, really) at your command prompt.

I feel like this is highly role-dependent. I learned on an HP and I have my TI-89 from high school sitting on my desk, because I thought it might be useful. I never touch it. I never do math that's more difficult than arithmetic, and if I needed to do calculus or algebra for some reason I'd reach for Mathematica -- it's not like I remember calculus class anyway.

Hell I tried to help someone younger with algebra and forgot FOIL. I'm a successful distributed systems engineer. Why do I need an engineering calculator?

Don’t mean to highjack but I was on the TI-89 camp, and I barely scratched the surface of its programming capabilities and memory. But it did help a lot with earthquake engineering and other mechanical dynamics courses in the university. Chugging a 6 kg laptop was impractical and this little TI was a beast!

> but only after loading additional software

which additional software?

Also, these two statements:

> it takes forever to use them to calculate useful things, and graphing is much better done on a computer

> the rewards are significant if you do any amount of calculation in your hobby or work. No, this is not replaced by typing "python" (or "bc", or anything else, really) at your command prompt

seem like they're at odds. If a computer has a considerable processing speed advantage and better display plotting capabilities, what's the value prop of the HP/RPL environment over python/bc/anythingElseReally?

(I have a 48G, clearly I may not have gotten high enough on the learning curve, your answer could be relevant to my decision to keep it or send it on into the world)

What do you think distinguishes the HP-50 from the 48, 49? I had a 48 and 49.

There were form factor and interface changes, the 50 is an ARM running a simulator vs the original Saturn architecture, there's the SD card.

What are the key software changes?

Better CAS?

I admittedly don't use it in any great depth (I did in the past), but the iHP48 is a very nice HP-48 for iOS. And it solves my primary complaint with the originals, a backlight.

> It's kind of like with gyms: what you get is what the market wants, and since the market doesn't know much, you get gyms full of useless exercise machines, because that's what people think a good gym should have.

I'm curious: what should a good gym have?

// many young people (yes, I know how that sounds) do not know how useful a good engineering calculator //

It's ok, I sound like that too. The problem is that in order to be acceptable for school use, calculators have to be so lobotomized that they are useless for real engineering work. The keyboard cannot be qwerty, it has to have lockdown modes which shut off functionality, etc etc.

Frankly, as a math teacher, I'd be just as happy if my students could program their calculators to help them on assignments and tests.

// I wish there was a good HP50G emulator for iOS//

A calculator has to have buttons man :-)

>steep learning curve

actually, shallow learning curve.

the steepness means "a lot of learning from a small amount of experience"

If the source is GPL, why not release it?

I have a Prime G2 and the RPN mode is just bad. It feels like it was an afterthought, and some things just don't seem to work properly in that mode.

My 48G+ is a much, much better RPN calculator.

The Prime G2 is also missing the equation library from the 48G+, which I found weird. Maybe they expect you to download what you need instead of using space in Flash for it.

I'd recommend eBay, too, if you're within the continental US. This might be sacrilege, but after using a TI-89 I shifted to an TI Nspire CAS, since it has one of the highest-resolution screens in the market and still uses AAA batteries – I paid only $25 on eBay.

I have an HP Prime (and older ones such as the 48gx). I don't know why they remove the "undo" button from the Prime since it is necessary when perform mistakes.

A physicist working on the project used this to compute the space contraction for the https://en.wikipedia.org/wiki/Oh-My-God_particle, which presumably traveled at 0.9999999999999999999999951 time the speed of light. You cannot do that with your HP48GX directly using standard formulas, because it only has 12 digits of precision.

> Seems like a really nice effort.

Does it? Another powerful calculating engine trapped behind a skeuomorph interface?

Here[1] is a really nice effort that, sadly, hasn't been updated in 14 years and only runs on Windows. It's a wonderful 606kB math REPL that can probably do everything DB48X can do, except it foregoes all the 1970's portable calculator nonsense, making it about a thousand times more useful.

I have a nascent clone of this written in Rust using egui and rug, that is currently stalled because -- on bleeping Windows -- the former has problems with MinGW the latter has problems with MSVC... which makes me want to tear my hair out. I wait, patiently, for egui to get their MinGW ducks in a row because I have no hope that the GMP/MPFR/MPC stack is ever going to work on MSVC in my lifetime.

[1] https://speqmath.com/

I feel the same way about not needing a physical calculator. I have an HP-48SX and an HP-15C Collector’s Edition. I enjoy these devices; they are high-quality and are exemplary products. However, as a professor I have regular access to my laptop, which can run circles around my handheld calculators. For quick calculations I open up the terminal and use the dc command, which is a command-line RPN calculator. For more involved computations, I have Python and Common Lisp REPLs, and I also sometimes use Microsoft Excel.

These days handheld calculators seem to be used the most in situations where people are restricted from using laptops and smartphones, such as during exams or in distraction-free settings. I think the reason Texas Instruments still has a viable calculator business is because TI markets heavily in the education market.

There is a free iPhone version as well (called DB40X). Maybe some day give it a try?

This is also an iphone app.

Same. Love calculators and used to flirt with the idea of buying an old HP graphing but the app scratches that itch. Once you learn RPN it just feels so natural.

In theory yes. In practice, the TI 83/84 are probably not beefy enough, and the NumWorks has a keyboard that makes the endeavour really complicated.

That’s cool!

> Where's the apostrophe (equiv. to quote in lisp)? That should be an easily accessible key not buried in a menu.

The apostrophe is on the XEQ key of the DM42, or "F". But in RPL, it is not to quote like in Lisp, but to introduce algebraic expressions (although it does quote names as a side effect).

On the simulator / web site, the symbol on the key looks like this: [' ()], it is on the second row on the rightmost column, see https://github.com/c3d/db48x/blob/stable/DB48X-Keys/DB48X-Ke....

The key is labeled like this because it serves a dual purpose to accommodate the smaller number of keys on the DM42 relative to the HP48. It adds a tick when not inside an expression, which in RPL begins an algebraic expression. When you are inside an algebraic expression, then you don't need tick anymore, so the key inserts parentheses inside.

> - Why did he swap the log keys?

Because I personally prefer to have exp and ln rather than ln and log. I also would prefer to have y^x as a primary, unshifted key, and this change is coming soon.

But I recognize that keyboard layout is a personal preference, so I'm currently working on making this customizable. Recently, "User mode" has been introduced, which lets you reconfigure the keyboard the way you want. So if you want to restore decimal LOG as the primary key instead of EXP, then do this: 'LOG10' 24.1 ASN. You should be able to restore EXP to the original position with 'EXP' 25.2 ASN, but there is bug with shifted user keys that I need to fix. This should be fixed in the next release.

In addition, the very next release should offer three layouts:

1) One that is maximally compatible with DM42 / HP42, which I assume is what you want.

2) One that corresponds to the current layout, so that people with existing overlays can keep them.

3) One that corresponds to a new iteration of the key layout that is better suited for DB48x, which is currently being discussed on the HP Museum forum.

https://en.wikipedia.org/wiki/Erable

Free42 is more faithful to the original 42 than this is to the 48. Free42 also has an infinite stack hack which is a nice bridge to those accustomed to the RPL.

This is annoying to installe and not really completed (this is a much much larger endeavor than the 42). Its also very disorienting at first until you figure out the UC

That said, its good enough that I use it on my swisimicro rather than my 48s because the screen is much better

Well, it's based on the hp48 instead of the hp42, for one. Though that button layout is not that close to the 48, either.

Its annoying to instal, I eventually got it to work on my calculator (DM42) from the binaries.

The biggest thing is making sure all the firmware of the DM is upgraded

Same, shows JavaScript error:

"Uncaught ReferenceError: SharedArrayBuffer is not defined at db48x.js:615:40"

Both in Chrome and Firefox (both are up to date to versions way beyond where SharedArrayBuffer should have been introduced)

I think they should either use ArrayBuffer, or use https instead of http, apparently SharedArrayBuffer has security restrictions

It needs https.

Use https://48calc.org/db48x/index.html

Apparently, for security reasons, your server needs to add certain headers if you want to use SharedArrayBuffers.

https://hacks.mozilla.org/2020/07/safely-reviving-shared-mem...

This works with Firefox 132.0, tested on Fedora 41 right now.

There are three floating-point representations:

- A variable-precision decimal floating point that uses base-1000 internally with 10 bits for 1000 values instead of 1024, so reduced memory waste, and LEB128 for size and exponent encoding. So 1.23 is 5 bytes, and each decimal value has its own precision. The precision only affects computations, not stored objects, so you can adjust the precision for each step of a computation.

- IEEE754 hardware accelerated 32-bit and 64-bit binary floating point.

In line with RPL, there are many other object types, including arbitrary-precision integers (123 is 2 bytes, 100! is 68 bytes), symbolic expressions, programs, lists, and so on.

Sorry about that ;-)

It's a tribute to Hewlett and Packard, but taking the first names, and with the individuals reversed for balance.

I do not believe there is any possible infringement on a clearly new design, even if that design is intentionally reminiscent of the HP logo.