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HP 50g - How to log and edit RPN expression entry?
01-16-2016, 05:15 AM (This post was last modified: 01-16-2016 05:41 AM by jimbo1qaz.)
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HP 50g - How to log and edit RPN expression entry?
I recently moved from a heavily modded TI84+ (slightly unstable) (BASIC causes brain damage) to an HP 50g (cheapest option available XD ). I've had it for a few months, but never really got familiar in practice. This is my first CAS calculator, but seems rather awkward to use.

Integration is a bit tricky: Symbolic home screen, step-by-step symbolic equation editor, numeric equation editor, what else? Also, definite integrals from the home screen require << a b INTVX PREVAL >> . Is there a way to perform fast home-screen definite integration without first INTVX-ing?

Loading the graphing screen is slower than TI-84+ Classic mode. Graphing entry forces you to name all Y-values. Cancelling a graphing operation takes an entire second. One hard issue I encountered is that the slope field only works from the <F4 2D/3D menu, not the <F1 Y= menu.

But these questions are for another time...

The biggest problem I have right now, is that when entering expressions in the RPN home screen, numeric values are not preserved when typing. This makes editing symbolic expressions suboptimal, and numeric expressions completely impossible.

On the TI-84+, I frequently performed textual equation editing directly from the home screen. Although limited (graph variables) and error-prone (parentheses), it was at least functional.

As an analogy, RPN is similar to writing a desktop program by typing code directly into a compiler. You cannot easily undo mistakes along the process, nor can you iterate on the original code after running it. RPN is actually worse, because you can't even see the full expression as it's being written (for numeric values).

I discovered you can perform RPN entry in RPL tags << >> instead, duplicate the expression, then evaluate. However, this requires manual duplication, introducing a source of human error. Also, unit conversions and calculus functions behave differently in RPL (I haven't figured out). Most importantly, you no longer get intermediate values, and the wall-of-text entry is difficult to read.

You can also duplicate expressions using ENTER, then perform operations on the lower copy. Still that's error-prone, and doesn't preserve variables.

Is the proper solution to use algebraic (backtick) expressions in RPN mode? (Somehow, RPN single-ticks do not support typing 2x for 2*x. Inconvenient.)

Algebraic expressions can be constructed and edited in the equation editor. But I find the equation editor to be tedious. Also, they're simplified just like RPN.

This only allows editing, and does not directly enable a full history.

Is there any program that collects RPN input into a RPL block, and allows you to recall RPL expressions? or something? Similar to Algebraic?
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HP 50g - How to log and edit RPN expression entry? - jimbo1qaz - 01-16-2016 05:15 AM

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