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stack lift and change sign
09-01-2014, 11:38 AM
Post: #54
RE: stack lift and change sign
(09-01-2014 10:36 AM)walter b Wrote:  Thus, already the HP-45 featured a very (!) useful key labeled Σ+. It was the key every experimentalist was waiting for. It solved that problem once and forever and in a reasonable way - with Σ- inverting it.

I'm not disputing the benefits of Σ+, it was quite amazing in its time, although maintaining all the data individually is a significant step forward on the RPL devices.

I really just disagreeing with it's stack behaviour:

Code:
Y X Σ+ -> Y n
          with stack lift disabled

is kind of weird. Surely, better is:

Code:
Y X Σ+ -> ∅

which is a consistent improvement. UNDO or LAST returning the two argument to the stack for the Σ- error correction is better than playing stack games. If the display of n is important, make it a temporary on the screen but don't put it on the stack.


- Pauli
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Messages In This Thread
stack lift and change sign - Thomas Klemm - 08-10-2014, 09:48 AM
RE: stack lift and change sign - walter b - 08-10-2014, 11:44 AM
RE: stack lift and change sign - d b - 08-11-2014, 06:08 AM
RE: stack lift and change sign - Paul Dale - 08-11-2014, 06:21 AM
RE: stack lift and change sign - walter b - 08-27-2014, 11:30 AM
RE: stack lift and change sign - d b - 08-27-2014, 02:32 PM
RE: stack lift and change sign - walter b - 08-27-2014, 03:57 PM
RE: stack lift and change sign - Andreas - 08-27-2014, 07:40 PM
RE: stack lift and change sign - d b - 08-29-2014, 04:45 AM
RE: stack lift and change sign - walter b - 08-29-2014, 09:15 AM
RE: stack lift and change sign - walter b - 08-29-2014, 09:47 AM
RE: stack lift and change sign - walter b - 08-29-2014, 04:11 PM
RE: stack lift and change sign - walter b - 08-29-2014, 07:54 PM
RE: stack lift and change sign - walter b - 08-31-2014, 06:23 AM
RE: stack lift and change sign - walter b - 08-29-2014, 08:21 PM
RE: stack lift and change sign - Les Bell - 08-11-2014, 01:41 AM
RE: stack lift and change sign - Paul Dale - 08-11-2014, 06:44 AM
RE: stack lift and change sign - walter b - 08-28-2014, 08:33 PM
RE: stack lift and change sign - Paul Dale - 08-28-2014, 10:05 PM
RE: stack lift and change sign - walter b - 08-29-2014, 12:55 PM
RE: stack lift and change sign - walter b - 08-29-2014, 01:25 PM
RE: stack lift and change sign - walter b - 08-29-2014, 02:04 PM
RE: stack lift and change sign - walter b - 08-29-2014, 02:25 PM
RE: stack lift and change sign - walter b - 08-29-2014, 03:05 PM
RE: stack lift and change sign - Paul Dale - 08-31-2014, 07:25 AM
RE: stack lift and change sign - RMollov - 08-31-2014, 09:40 AM
RE: stack lift and change sign - walter b - 08-31-2014, 11:26 AM
RE: stack lift and change sign - walter b - 08-31-2014, 08:50 PM
RE: stack lift and change sign - Paul Dale - 08-31-2014, 09:52 PM
RE: stack lift and change sign - walter b - 09-01-2014, 10:36 AM
RE: stack lift and change sign - Paul Dale - 09-01-2014 11:38 AM
RE: stack lift and change sign - walter b - 09-01-2014, 06:56 PM
RE: stack lift and change sign - walter b - 08-29-2014, 09:21 PM



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