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Full Version: Calculations history in RPN mode,
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Is there a way to have RPN mode keep the calculations you have just performed in the stack, preferrably on the other side of screen, like algebraic mode does?

I would like to get used to RPN and in case I may enter the wrong numbers or maths sign, I would like to know what I entered.

Algebraic mode has this feature, I get that, but programming the calculator doesn't seem to lend itself to ALG mode very well, programming seems to be geared towards RPN mode.
The short answer is no. By its nature, objects on the stack are "consumed" when a function is performed and are (usually) replaced with the answer as the stack is shifted down. The RPN models only had a four register hardware working stack and would not have had room for a history anyway. The later RPL models (like the HP 50g) had a stack that was only limited by available memory but the philosophy was similar to the RPN models in maintaining a stack discipline that replaced arguments with the answer.

On the HP 50g, the keyboard command CMD (left-shift, HIST) will show you the last four arguments entered.
One way would be to use a printer. E.g. with Olivier De Smets Android app go41cxt you could have the printer in Trace-mode, and then follow the history of your calculation.
Of course this works with the original printer as well, or with the HP-97 (and other calculators with inbuilt printer).

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Cheers, Thomas
"Modern" RPL calculators like the 48G or 49/50g also have an undo function where you can undo the last operation (stock firmware) or even more than one step (newRPL).
As TomasF suggests, any RPN hardware with a printer will do.

That's the reason for the TRACE mode of these printers, to have a printed trace of each operation in order to follow and be able to verify all operations.
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