Anything that goes beyond what that calculator's UI can reasonably handle is going to end up in a Jupyter notebook or something like that.
[0] https://thomasokken.com/free42/ I should send them a donation.
[1] https://literature.hpcalc.org/community/hp42s-om-en.pdf followed by https://literature.hpcalc.org/community/hp42s-prog-en.pdf
Handheld calculators are nice, but outside of exam settings, I could use a smartphone or a computer, though calculators are nice when I want to work distraction-free through something that requires performing calculations. I believe this is why HP largely exited the calculator market: HP's target market was professionals, and cheap computers and smartphones killed the calculator market for them, similar to how electronic calculators killed the slide rule. Texas Instruments, however, is still in the calculator business, largely due to their successful courting of American middle and high schools, as well as ETS and other testing agencies, beginning in the 1990s. I don't know the situation in Japan regarding calculator usage, but I see Casio scientific and graphing calculators proudly displayed at electronics stores such as Yodobashi Camera and Bic Camera.
HP-35 (1972, first scientific, first in space) - in leather case
TI-30 (1976, first low-cost scientific)
HP-12C (1981, financial, c. 2000 remanufacture)
HP-15C (1982, advanced scientific) - in leather slipcase
HP-16C (1982, computer programming) - in leather slipcase with manual
TI-30 SLR (1982, TI’s first solar-powered scientific)
HP-17B II (1990, financial)
TI-85 (1992, TI’s first with link port)
TI-82 (1993)
TI-92 (1995, TI’s first with computer algebra system)
honestly, I think it makes no sense to spend more than 30$ on a calculator if it can't do symbolic math.
The way you input things like division, integrals, matrix, etc. on newer calculators like the nspire is far superior than the older calculators (eg. ti-84, ti-89, etc.). They look like how you write them on a blackboard instead of relying on purely parentheses or "," and ";" to separate parameters. It's like going from Excel to Mathcad
I still have my TI-85, but I essentially haven't used it since I left college. For 99% of what I need, I use either Python, or what's built into Firefox (e.g. unit conversion), or DDG. For that last 1% (e.g. full CAS functionality), I tend to grab whatever web-based non-AI tool is handy.
At that point I’m either using the stock iOS calculator or iHP48, HP48 clone.
It mostly depends on which page of apps I’m on and which is closest.
I like the unit conversion on the iOS calculator, easier to use for trivial calcs than the HP.
Biggest gripe on iOS is a single memory. On the HP I’m mostly hooked on the infinite stack, and that’s why I use it over the HP-42 clone app I have as well.
Or often just a python repl