+- HP Forums (https://www.hpmuseum.org/forum)
+-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html)
+--- Forum: General Forum (/forum-4.html)
+--- Thread: Calculations history in RPN mode, (/thread-17064.html)
Calculations history in RPN mode, - matalog - 06-06-2021 09:20 PM
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.
RE: Calculations history in RPN mode, - Steve Simpkin - 06-06-2021 10:51 PM
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.
RE: Calculations history in RPN mode, - ThomasF - 06-07-2021 06:16 AM
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).
[attachment=9548]
Cheers, Thomas
RE: Calculations history in RPN mode, - SammysHP - 06-07-2021 01:11 PM
"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).
RE: Calculations history in RPN mode, - C.Ret - 06-07-2021 06:35 PM
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.