Finally discovered something a TI-30 can do that an RPN calculator can't

[Dave Britten]

From Radio Shack's "Understanding Calculator Math" (1978).

https://i.imgur.com/xn7Nc99.jpg

It's a rather enjoyable light collection of applied math. This is from the puzzles and games chapter.

[pinkman]

So many years in love with RP[N|L] and I finally discover I missed the game that was hidden in every stupid desktop infix calculator!
Anyway, the idea is pretty brilliant.

[Steve Simpkin]

Very clever! Of course this game will no longer work with most modern scientific (or graphing) calculators that show you what you have entered so far.

[pinkman]

Yes.
Even the standard iPhone calc app cannot be used, it highlights the selected key.

[Dave Britten]

(05-29-2020 04:42 AM)Steve Simpkin Wrote:  Very clever! Of course this game will no longer work with most modern scientific (or graphing) calculators that show you what you have entered so far.

Yeah, it's a very clever game for this specific subset of old machines. Of course, I haven't tried playing it, so I don't know how deep the game actually is. (i.e. can it be trivialized like Tic-Tac-Toe?) The rules might need a few tweaks to give it any longevity.

[Jlouis]

Thanks Dave!

A very good reason to clean my old TI-30 and play this game!

Cheers

JL

[Jim Horn]

Unless the RPN calculator can be programmed to emulate a TI-30, as I programmed an HP-67 to be an AOS calculator back in 1977.

[twoweims]

(06-08-2020 09:28 PM)Jim Horn Wrote:  Unless the RPN calculator can be programmed to emulate a TI-30, as I programmed an HP-67 to be an AOS calculator back in 1977.

.

[attachment=8560] YOU DID WHAT??!

[toml_12953]

(06-08-2020 09:28 PM)Jim Horn Wrote:  Unless the RPN calculator can be programmed to emulate a TI-30, as I programmed an HP-67 to be an AOS calculator back in 1977.

No no no! You went the wrong way!

[Gene]

Jim's AOS program for the HP-67 has been modified to run on the HP-41C and is present in the 67FUN rom for the HP-41CL and emulators.

The manual for this rom and a listing of all programs, including Jim's very nice AOS program, can be found here:

67FUN rom manual.

[Jim Horn]

OK, I confess. The reason for the AOS '67 program was two fold. First, the algorithm to parse and execute a general infix notation was part of a programming course I took in 1972 (!) and I wanted to see if it was possible to squeeze that into the HP-67's 224 steps. Also, in those days the level of energy shown by proponents of HP's RPN versus TI's AOS was almost comical. So having the HP-67 be able to do both (which the TI machines at the time could not do) was something of a lark.

Of course, on the actual 10 program instructions per second speed of the HP-67, using this program was an exercise in massive patience as there was a serious delay in everything it did. Today's simulators and even the HP-41's greater speed help a lot in that regard!

So, the program wasn't written as a serious tool for practical use as an infix notation calculator. But it does illustrate some of the tricks we all had to use back then to wring every bit of performance we could out of the limited resources we had back then.

Regarding speed - the fastest factoring program ever written for the HP-67 took about 165 minutes to test 9999999967, the largest integer prime it could handle. My HP 50g verifies that it is prime in under 1 second, a roughly 10000 times improvement. And the HP Prime is reportedly much faster still. "Good old days" my foot!

[Eddie W. Shore]

This game can be played on a four-function calculator (without the power function), the chain operating system instead of AOS changes the dynamics of the game.

[Gene]

I plan to write a game to do this on the HP 41 that mimics the AOS. I don't think it will be too difficult.

[Dave Britten]

(06-14-2020 02:59 PM)Gene Wrote:  I plan to write a game to do this on the HP 41 that mimics the AOS. I don't think it will be too difficult.

Yeah, should take about 5 minutes to write, and that's budgeting time for finding the 41 and possibly changing its batteries first.

LBL "GOTCHA"
SF 27
STOP
LBL A
STOP
+
RTN
LBL B
STOP
-
RTN

That's like half of the program right there. Player 1 enters a number, presses A-F to select an operation, player 2 enters a number and presses R/S.

[Gene]

Ah but player 2 can't simply enter a # and press R/S because they have to choose an operation to be performed next if they don't lose.

But a variation like that... could make it a one player game where the HP41 plays against you too.

[toml_12953]

(06-09-2020 11:26 PM)Jim Horn Wrote:  Regarding speed - the fastest factoring program ever written for the HP-67 took about 165 minutes to test 9999999967, the largest integer prime it could handle. My HP 50g verifies that it is prime in under 1 second, a roughly 10000 times improvement. And the HP Prime is reportedly much faster still. "Good old days" my foot!

They were the good old days. We had to wait hours to get time on a mini or days to submit a punched card deck for the mainframe. When the HP 65 came along, you could get the answer in a few minutes. It was a huge deal for us engineers back then. Of course you can't compare those old machines to the computers (including smartphones) of today but in the context of their time, they were such a boon that kids today (anyone under 40) can't even imagine what it was like.

[Jim Horn]

Oh, absolutely! They were *very* good old days, at the time. The level of excitement we had with these new devices was terrific. But that's still true for those who dive into today's advances as well. Hey, I even get paid to do so designing state of the art avionics and such.

The details may change but the basics are forever. Hooray for everyone here!