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Can we have RPN back?
01-26-2014, 08:57 PM (This post was last modified: 01-26-2014 09:00 PM by Han.)
Post: #12
RE: Can we have RPN back?
RPN made sense only on hardware that was limited in resources. RPL makes more sense on a system with a larger display and much more memory. And as technology improves, RPL will be much more robust while RPN feels extremely limited. While complex operations can be carried out with 4 levels of stack, why would you want to limit yourself to only 4 levels? In really complicated formulas, I would rather just do my computations and use however many levels I needed and not have to spend any time thinking about which innermost calculation has to be performed first so that I don't lose data due to a limited stack.

DUP on ENTER, while it may be useful, makes very little sense if you think of the X register as an actual stack level. Instead, the X register is essentially shared with the command line -- so that you really only have 3 true levels. This is really the only way to explain the DUP on ENTER effect -- that the X register and the command line are one and the same, and that ENTER was really just DUP. In RPL, the command line is separate from the stack.

Quote:
Quote:Stack lift on swap *does* work on e.g. the 48G, so I consider this to be a bug in the Prime, not its intended behaviour.

It doesn't on the 49 and later where it is mapped to the right arrow.

SWAP was mapped to the right arrow on the HP48 as well. In order to actually swap the current contents of the command line with level 1 of the stack, you actually had to execute the SWAP command by pressing [LeftShift][RightArrow] on the HP48. On the other hand, you could not do a swap by pressing the [RightArrow] (no shift) because this was a keyboard shortcut (as opposed to executing the SWAP command) unless the command line was cleared. The behavior of the [,] key on the HP Prime mimics the [RightArrow] key back on the HP48 (and later) models. The HP49 and HP50G no longer had a separate SWAP command shortcut like the HP48 -- all they had was the keyboard shortcut limited to [RightArrow] key.

Also, on the HP48 series, the command line was parsed and executed any time the user presses a key sequence corresponding to an RPL command. Thus, 2 3 + would automatically end the command line input after +. This is why 2 ENTER 3 + and 2 ENTER 3 ENTER + work the same way. Likewise, 2 3 [LeftShift][RightArrow] produces the same result as 3 ENTER 2 ENTER.

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Messages In This Thread
Can we have RPN back? - Tugdual - 01-26-2014, 10:24 AM
RE: Can we have RPN back? - Thomas Radtke - 01-26-2014, 05:42 PM
RE: Can we have RPN back? - Tim Wessman - 01-26-2014, 07:29 PM
RE: Can we have RPN back? - Tugdual - 01-26-2014, 05:45 PM
RE: Can we have RPN back? - Craig Thomas - 01-26-2014, 06:23 PM
RE: Can we have RPN back? - Joe Horn - 01-27-2014, 03:58 AM
RE: Can we have RPN back? - Thomas Radtke - 01-27-2014, 06:32 AM
RE: Can we have RPN back? - Joe Horn - 01-27-2014, 07:56 AM
RE: Can we have RPN back? - Thomas Radtke - 01-28-2014, 06:14 AM
RE: Can we have RPN back? - Tugdual - 01-26-2014, 07:02 PM
RE: Can we have RPN back? - Tim Wessman - 01-26-2014, 07:47 PM
RE: Can we have RPN back? - orcinus - 03-27-2014, 02:31 PM
RE: Can we have RPN back? - Tim Wessman - 03-27-2014, 03:58 PM
RE: Can we have RPN back? - Han - 01-26-2014 08:57 PM
RE: Can we have RPN back? - John R. Graham - 02-09-2014, 02:50 PM
RE: Can we have RPN back? - Craig Thomas - 01-26-2014, 11:53 PM
RE: Can we have RPN back? - Mark Hardman - 01-27-2014, 01:03 AM
RE: Can we have RPN back? - Craig Thomas - 01-27-2014, 06:45 AM
RE: Can we have RPN back? - Tugdual - 01-27-2014, 09:24 AM
RE: Can we have RPN back? - Ivan Rancati - 03-28-2014, 06:29 PM
RE: Can we have RPN back? - Thomas Radtke - 03-28-2014, 06:41 PM
RE: Can we have RPN back? - Craig Thomas - 03-30-2014, 06:24 AM
RE: Can we have RPN back? - Tim Wessman - 01-27-2014, 03:45 PM
RE: Can we have RPN back? - rlinden12 - 02-04-2014, 11:28 PM
RE: Can we have RPN back? - Thomas Radtke - 02-05-2014, 06:28 AM
RE: Can we have RPN back? - Joe Horn - 02-05-2014, 10:01 PM
RE: Can we have RPN back? - Craig Thomas - 02-06-2014, 12:31 AM
RE: Can we have RPN back? - Steve Simpkin - 02-06-2014, 01:40 AM
RE: Can we have RPN back? - Steve Simpkin - 02-09-2014, 11:43 PM
RE: Can we have RPN back? - Han - 02-10-2014, 01:53 AM
RE: Can we have RPN back? - John R. Graham - 02-10-2014, 04:26 PM
RE: Can we have RPN back? - Han - 02-10-2014, 08:00 PM
RE: Can we have RPN back? - John R. Graham - 02-10-2014, 08:47 PM
RE: Can we have RPN back? - Steve Simpkin - 02-10-2014, 08:58 PM
RE: Can we have RPN back? - John R. Graham - 02-10-2014, 09:51 PM
RE: Can we have RPN back? - Tim Wessman - 02-10-2014, 10:00 PM
RE: Can we have RPN back? - John R. Graham - 02-10-2014, 10:14 PM
RE: Can we have RPN back? - Tim Wessman - 02-10-2014, 10:23 PM
RE: Can we have RPN back? - John R. Graham - 02-11-2014, 10:53 PM
RE: Can we have RPN back? - orcinus - 03-27-2014, 04:08 PM
RE: Can we have RPN back? - John R. Graham - 03-28-2014, 03:34 PM
RE: Can we have RPN back? - orcinus - 03-28-2014, 11:42 PM
RE: Can we have RPN back? - John R. Graham - 03-29-2014, 03:05 AM
RE: Can we have RPN back? - HP67 - 03-30-2014, 07:05 AM
RE: Can we have RPN back? - Jake Schwartz - 03-27-2014, 06:06 PM
RE: Can we have RPN back? - Tugdual - 03-29-2014, 12:21 AM
RE: Can we have RPN back? - orcinus - 03-29-2014, 12:45 AM
RE: Can we have RPN back? - Tugdual - 03-29-2014, 07:16 AM
RE: Can we have RPN back? - HP67 - 03-30-2014, 07:07 AM
RE: Can we have RPN back? - Joe Horn - 03-30-2014, 09:40 AM
RE: Can we have RPN back? - orcinus - 03-29-2014, 05:00 AM
RE: Can we have RPN back? - John R. Graham - 03-29-2014, 11:53 AM
RE: Can we have RPN back? - orcinus - 04-02-2014, 09:26 PM
RE: Can we have RPN back? - HP67 - 03-30-2014, 09:45 AM
RE: Can we have RPN back? - RyanB - 03-30-2014, 04:35 PM
RE: Can we have RPN back? - HP67 - 03-30-2014, 04:42 PM
RE: Can we have RPN back? - Joe Horn - 03-31-2014, 03:37 AM
RE: Can we have RPN back? - Han - 03-31-2014, 04:00 AM
RE: Can we have RPN back? - HP67 - 03-31-2014, 06:19 AM
RE: Can we have RPN back? - Thomas Radtke - 03-31-2014, 06:32 AM
RE: Can we have RPN back? - RyanB - 03-30-2014, 07:20 PM
RE: Can we have RPN back? - Matt Agajanian - 03-30-2014, 08:02 PM
RE: Can we have RPN back? - Tim Wessman - 03-31-2014, 03:01 PM
RE: Can we have RPN back? - Steve Simpkin - 03-31-2014, 04:22 PM
RE: Can we have RPN back? - Matt Agajanian - 04-02-2014, 05:31 PM



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