5 ms·

Reverse polish notation? I was taught this for UK A-level computer science (age 16).

disabled 5y ago
I am an American (culturally) who lives in Croatia, so I am aware of the educational system in mainland Europe and also the UK. In the US, we only learn "traditional" (non-RPN), calculator entry, and this is even at university level! But, calculators are only allowed for checking our work in mathematics courses, at both secondary and university levels, and never for quizzes/exams/proctored material. But, computer science in secondary school (high school) may be an exception as RPN is a classic example of the usage of stacks. I think a lot of this has to do with contracts that school districts in the United States have with the calculator ("educational") companies, which have educational material (which is integrated into standard textbooks that you use for the school year) to assist in teaching calculator entry techniques and usage. They also get quite good deals on Texas Instruments calculators, which have no RPN features whatsoever. I really do think that kids (and their educators) not knowing RPN is a huge disservice. I personally taught myself RPN on an HP 50g while doing my undergraduate electrical engineering coursework, specifically during circuit analysis 1 and electromagnetics 1. Everyone else was using a TI-89 (Texas Instruments 89) and they were learning off of each other how to use various techniques to solve problems, while I was alone with learning stuff on the calculator. Because of the complex entry of various different unit types and integrals, it was a pretty steep learning curve, on the HP 50g, and it took me about a month to get proficient at it.(This is difficult to do on top of the coursework because you are going through your weed-out courses at a "traditional" engineering program where over half the class will not pass these courses! As in, they will either get a D+ or lower, or get a W--a withdrawal grade). But, it saved me and paid off on exams, while I was using the HP 50t, as people made all sorts of errors on their TI-89s with these really difficult equations, and got major points off. Although many different types of errors are made, a critical one is a missing parenthesis, which causes a ton of points to be taken off on an exam. Also, people with TI-89s ran out of time "double checking for errors" (such as for a missing parenthesis) on exams, and this alone can be the difference between passing and failing a course. The way the stack works on a HP 50g seriously reduces errors. My (American) father also taught himself RPN at university when he was studying to become an accountant. But, in his case, it was easier to learn, although still not necessarily easy.
- wtallis 5y ago
  The benefits of the units system in the HP 48/49/50 series really cannot be overstated. You don't just get free conversions between compatible unit types, you also get realtime type checking to prevent invalid operations on quantities with incompatible units. This eliminates a very common source of errors, and also encourages more rigorous labeling of quantities with units when you're working on paper. The TI-89 technically can also compute using quantities tagged with unit information, but the UI for it is too convoluted to be useful.
kwhitefoot 5y ago
Me too. And this was in 1972.

I am an American (culturally) who lives in Croatia, so I am aware of the educational system in mainland Europe and also the UK. In the US, we only learn "traditional" (non-RPN), calculator entry, and this is even at university level! But, calculators are only allowed for checking our work in mathematics courses, at both secondary and university levels, and never for quizzes/exams/proctored material. But, computer science in secondary school (high school) may be an exception as RPN is a classic example of the usage of stacks. I think a lot of this has to do with contracts that school districts in the United States have with the calculator ("educational") companies, which have educational material (which is integrated into standard textbooks that you use for the school year) to assist in teaching calculator entry techniques and usage. They also get quite good deals on Texas Instruments calculators, which have no RPN features whatsoever. I really do think that kids (and their educators) not knowing RPN is a huge disservice. I personally taught myself RPN on an HP 50g while doing my undergraduate electrical engineering coursework, specifically during circuit analysis 1 and electromagnetics 1. Everyone else was using a TI-89 (Texas Instruments 89) and they were learning off of each other how to use various techniques to solve problems, while I was alone with learning stuff on the calculator. Because of the complex entry of various different unit types and integrals, it was a pretty steep learning curve, on the HP 50g, and it took me about a month to get proficient at it.(This is difficult to do on top of the coursework because you are going through your weed-out courses at a "traditional" engineering program where over half the class will not pass these courses! As in, they will either get a D+ or lower, or get a W--a withdrawal grade). But, it saved me and paid off on exams, while I was using the HP 50t, as people made all sorts of errors on their TI-89s with these really difficult equations, and got major points off. Although many different types of errors are made, a critical one is a missing parenthesis, which causes a ton of points to be taken off on an exam. Also, people with TI-89s ran out of time "double checking for errors" (such as for a missing parenthesis) on exams, and this alone can be the difference between passing and failing a course. The way the stack works on a HP 50g seriously reduces errors. My (American) father also taught himself RPN at university when he was studying to become an accountant. But, in his case, it was easier to learn, although still not necessarily easy.

wtallis 5y ago
The benefits of the units system in the HP 48/49/50 series really cannot be overstated. You don't just get free conversions between compatible unit types, you also get realtime type checking to prevent invalid operations on quantities with incompatible units. This eliminates a very common source of errors, and also encourages more rigorous labeling of quantities with units when you're working on paper. The TI-89 technically can also compute using quantities tagged with unit information, but the UI for it is too convoluted to be useful.

kwhitefoot 5y ago

Me too. And this was in 1972.