This is similar to programming language discussions: any programming language can be discredited by saying "but I can do all that in assembly/C/whatever". Yes, you can, but perhaps there are better ways to do it.
for the engineering calculators, it seems the advantage is that some people learnt to use them in school and really love using them? that's great, I'm tempted to look into them myself, because it does sound cool to have a small device that does that sort of thing while I'm reading a book. but the truth is that for me, both at work and at home, my laptop is never more than 5 seconds away from showing me a repl, so maybe I'm not the target audience.
1. What happens if I rotate binary pattern 1001 right by 3 positions on a 18-bit PDP-9?
RPL code: 18 STWS 2#1001 3 RRC
Result: #8001 in base 16, #1000 0000 0000 0001 in base 2.
What about if I do this on 6 36-bit words? RPL code: 6 36 * STWS 2#1001 3 RRC
Result: #20 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0001
2. What is the symbolic expression of the determinant of some 2x2 matrix? Program: [[1 y]['2+x' b]] DET
Answer: 'b-(x+2)·y' (shows graphically on calculator screen)
3. What is the output voltage of a voltage divider with input voltage 100V, R1=4kΩ, R2=10Ω Program: R1=4_kΩ R2=10_Ω V=100_V 'ROOT(ⒺVolt Divider;[V1];[1_V])' EVAL
Result: [ V1=99.75 V ]
Note that ⒺVolt Divider is a built-in equation, but you can of course put your own.
4. Verify if Ramanujan constant exp(sqrt(163)*pi) is an integer. Program: « 'exp(√ 163·Ⓒπ)'60 PRECISION →Num FractionalPart »
Result: -7.50E⁻¹³, so no, not an integer, but really close
5. Verify Maxwell's value for the speed of light, epsilon0 * mu0 * c^2 = 1. Program: '(√(Ⓒε0·Ⓒμ0))⁻¹' →Num
Result: 299 792 458.00 m/(F↑(¹/₂)·H↑(¹/₂))
Convert to SI units: UBASE
Result: 299 792 458. m/s
Convert to feet per second: ³⁷⁴ ⁷⁴⁰ ⁵⁷² ⁵⁰⁰/₃₈₁ ft/s or 983 571 056.43 ft/s.
(if you subtract the Ⓒc constant, you get -0.00031 11057 21 m/s)
6. Check the Collatz conjecture on 989345275647 Program: « if dup 1 ≠ then if dup 2 mod then 3 × 1 + else 2 ÷ end Collatz end » 'Collatz' STO 989345275647 Collatz
Result: 1 (conjecture is verified)
7. Given that it's now Nov 7, 00:07:51 and that a program I started on Nov 1st at 23:15:27 just finished, how long did it run? Program: 20241107.000751_date 20241101.231527_date - 1_h convert UVAL →HMS
Result: 120:52:24
(the "1_h convert UVAL →HMS" should really just be →HMS, but at the moment, →HMS is not smart enough to convert from days)What impresses me in this discussion is how coy everybody has been about the actual benefits of these devices.