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As a teen in the late 80's I had an HP calculator that I programmed to compute molecular weights given an input string like "H2SO4". It felt like having a secret superpower, especially when I participated in competitive exams. I was a very straightlaced kid and would not have used the program if it such things were explicitly forbidden, but as far as I could tell, they never were.




Reminds me of when I write a j2me app for matrix diagonalization because we could use the old feature phones as calculators. Nobody thought we'd be mad enough to use those to cheat...

Do you still have the source code for the j2me app?

I hadn’t yet learned to program back when I was still using a feature phone, but I have a lot of fond memories of J2ME applications that I installed on my phones. Mostly games, of course.

I encourage anyone that wrote J2ME games and utilities, no matter how small or big, to upload the source to GitHub :)


That one would be definitely lost to time...

Yeah makes sense. I have very little left of my early stuff too, heh

well a lot of bio info stuff are still using java.

But surely not so much J2ME for feature phones stuff right? Those bio info stuff are probably rather desktop applications.

they are mostly terminal with some gui optinally

Did you tell your teachers about your superpower?

But normally it depends on the subject and if the automation/machine solves the primary skill being teached or if its just a "secondary/tertiary" skill. Are you in a Calculus 101 class? Calculators like TI-89 are likely to be prohibited when examining for deriving analytical solutions for derivatives and integrals.

Statistics, Physics or any other subjects that needs applied maths? Such a calculator is probably a minimum requirement to take the course.


My HP-49g+ was definitely load-bearing going through EE. I was never much good at memorizing big sheets of formulas but I was pretty good at memorizing a couple of simple differential equations (e.g. I(t) = C dv(t)/dt was easy, v(t) = v_s * e^(-t/RC) wouldn't stick). So I'd just... derive all of the "special case" formulas from scratch during the exam. Usually they were simple enough that I could just get them into the right form but I'd lean on my calculator doing the symbolic integration for me when they weren't.

The other thing it was awesome for was solving systems of linear equations. I could do the nodal or loop analysis just fine, I'd write down the matrix that represented the system of equations and then just punch that matrix in and invert it.


You did the capacitor DE in your head? The analytical solution requires a “trick” (integrating factor) usually taught in an intro DE class.

It became second nature pretty quickly! Dunno what to tell you, my brain's wired funny :D

The day when the relationship between s in a Laplace transform and d/dt finally clicked was also a really excellent day :D


I was on pretty good terms with my chemistry teacher, so...maybe? It's been a while, but I don't remember either showing it off or taking pains to keep it secret. To adults, that is; my nerdy friends and I delighted in showing off the cool stuff we did with our calculators.

I vaguely remember thinking that one likely reason shortcuts like mine were not prohibited was because no one in charge suspected that such things were even possible with current technology, or if they were, that a child would be able to exploit it. But as long as I kept to the letter of the rules, I considered myself ethically in the clear.


> But as long as I kept to the letter of the rules, I considered myself ethically in the clear.

Yeah, totally, just to be clear I'm not judging.

In fact, if you programmed it to handle those operations, one could argue you had already learned a big chunk of what was going to be measured in the exams.

Kind of similar to the paradox of creating and using cheat sheets, is highly likely you're accidentally learning about the subject matter in the process of writing the sheet, sometimes up to a point where the cheat sheet is not necessary anymore.


> Kind of similar to the paradox of creating and using cheat sheets, is highly likely you're accidentally learning about the subject matter in the process of writing the sheet, sometimes up to a point where the cheat sheet is not necessary anymore.

The problem is (example from mathematics): even if you are capable of deriving some formula (you thus understood the topic well), it takes a lot of time in the exam. Looking at the cheat sheet is much faster - in particular when the time is somewhat precious in the exam.


A related personal story: During my statistics course in high school, we discovered that the TI-89 had some statistical functions that the TI-83 didn't have. So, the rule was that if we wanted to use the TI-89 ones, you had to write an application for the TI-83 one. It was a great way to really learn the algorithms.

Stuff like that seems harder to do than learning the damn thing correctly

I always felt (and my maths teachers agreed) that if I understood something sufficiently to automate it, I’d proved my point and didn’t need to do the rest of the exercises.

Edit: Automate in the sense of coding it myself, not in the sense of downloading some software.


I could do it correctly from the get-go. The program just saved me from drudgery many times over. Probably enough times to recoup my time investment to create the program, but in any case I enjoyed coding for its own sake.

I you like Chemistry, then yes. If you like programming but dislike chemistry, then no.

The calculator tricked them into studying. Same trick as the "one note card, front back" but in this case accidental.



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