HP 50g - How to log and edit RPN expression entry?

[Bob Frazee]

My first 2 calculators were the TI SR10 and SR11, from the early 70's. An instructor in one of my engineering classes had an HP 45, which had all the bells and whistles of that era. I was hooked. Learning how to manipulate the stack took a little bit of doing for me, but once mastered, I marveled at the ease of doing manual calculations with a stack (no parenthesis), and still today I prefer RPN/RPL over algebraic for manual calculations.

Stack calculations require a different mind set than algebraic. You Must understand how the stack operates, or you'll just frustrate yourself. I visualize the stack as just a stack of numbers, one on top of the other. RPN generally implies a 4 level stack, RPL generally implies an infinite stack (at least until you run out of memory). You have more instructions available to manipulate the RPL stack, but for both, you're generally working with the bottom 2 registers, RPN calls them X and Y, RPL calls them Level 1 and Level 2. There are tutorials on how the stack operates on this website. Please check them out.

For performance of user written programs (I program in User RPL on the HP50g, and TI Basic on the TI89 Titanium). I have found that the programs that I run (mostly engineering types), will generally get an answer within 2 or 3 seconds of each other, which is close enough for me. If you want to check one out, there is a program called FluidTI for the TI84+ (located at ticalc.org), and the same program called FluidHP for the HP50g (located at hpcalc.org). That should give you some idea of program performance.

Perservere in learning how the stack operates, and I don't think you'll regret your decision for purchasing the HP50g.