A modern reimplementation of HP’s RPL | Hacker News Reader

A modern reimplementation of HP’s RPL

rpl2.net

18 pointstagoregrtst4 comments

The HP48 series does exceptionally for basic scientific and engineering computation against computers with modern languages like Python. I could compute, script, and similar in it very efficiently. The problem is:

1) It's an integrated implementation. For example, RPL makes sense when you have the brilliant HP48 keyboard, and one-key access to many of the commands. It makes little sense if you're manually typing things. The number of keystrokes would go up 3-4 fold on a PC keyboard, and correspondingly, the number of stupid errors. You can't mistype a command if it's one button, or two keystrokes through the menu system.

2) Getting all of that integration, synergy, and polish requires a huge engineering and design effort and brilliant people. One-off projects can't meet it. A lot have tried.

3) The newest HP48 has a 4MHz 4-bit CPU, 128kb of user RAM, and a 131x64 pixel display. This isn't competitive in 2022.

I'd love to have a modern HP48, with an 800MHz CPU, gigabytes of RAM, and a high-res display, but to be at all worthwhile, it'd need to have the same quality keyboard, the same level of polish, the same community, and otherwise. I don't think that's gonna happen.

Unfortunately, HP calculators peaked with the 48GX. Newer models were faster but gradually lost the polish of the older models.

1) agreed. Thats why using the PC for basic calculations is so frustrating.

I really dont understand those who just “fire up an instance of python” to get a simple plot, never mind sin(58)

2) except for the keyboard, the DM-42 does a pretty fine job for what it is meant to do. Od put up with its keyboard before firing up python, thats for sure.

Numworks looks promising?

3) I wont get it to solve 1000x1000 matricies, and the HP48 always felt slower than the 28.

But as far as advanced graphing calculators, what’s really missing?

“ I'd love to have a modern HP48, with an 800MHz CPU, gigabytes of RAM,”

how I long for it though :S

“ HP calculators peaked with the 48GX.” HP as a company peaked around the same time :S

"RPL/2 or Reverse Polish Lisp/2 is a particular language, in the etymological sense of the term, which could be the result of the forbidden loves between Lisp and Forth. It takes in Forth its reversed polish notation and its stack addressing, but keeps only one standardized stack, and in Lisp, the power of its control structures."

Heh, forbidden love. Very cute, but the project seems to be inactive, and while the interpreter is free, the compiler is closed source and expensive. I think this is of not much interest unless you want to make an HP calculator clone or something. Otherwise the GNU Emacs calculator (calc.el) is afaict a lot more powerful than the old HP's were, and after that there are programs like Sage. Also, there are other RPL implementations out there.

I don't think I've used a calculator (including calculator apps) for anything more than simple purposes in years. Otherwise I end up using Python or whatever.

RPL is a favorite language of anyone who has had an HP calculator. Here you can try it out for yourself

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