Walkthrough of an RPL program for an RPN programmer

[Maximilian Hohmann]

Hello!

As I am quoted in the original and really excellent (!) post of this thread I need to comment quickly... (have been away for work last week and couldn't do it earlier).

Having read the posting and the replies shows me several things:

1. RPL is not RPL, not even within HP. While I was away last week the postman brought me yet another HP-19BII (with an uncracked battery door) which supposedly is RPL based. The examples from above which I tried on that calculator did not work. Especially not replacing the "Enter" key with blank spaces between the numbers which I had never heard about before. But then that calculator is only RPL internally with an RPN user interface. Following the thread however I read that there are really siginificant differences between RPL on various HP calculators.
2. RPL experts are not RPL experts, at least every one seems to use it in his own special way. Which makes RPL a very versatile tool but even harder to understand for laypersons. Because not only does one need a good understanding of the underlying principle/paradigm but one must be able to follow the thought patterns of the programmer. And all based on some extremely abbreviated and cryptic syntax. The best example for that is the expression « → a 'a+a' » of which, even after having read the whole thread, I still don't have the faintest idea what it might do.
3. RPL is definitely not for the occasional user.
4. Some RPL implementations are exrtemely powerful. 2500 built in functions. Impressive! But who remembers all those when he needs them? I certainly couldn't and the manuals don't make it very easy to find them either. There must be a reason why RISC has become the standard with microprocessors now: Keep it simple and keep the users in the loop.

Thanks for that great thread!
Max (still not convinced that RPL will ever be my thing)