LastXY Register for WP34S

[PANAMATIK]

(12-01-2014 06:45 PM)walter b Wrote:  Now, if I understood your suggestion correctly, with a LASTxy (or CPX RCL L) for error correction you'd push the previous (erroneous) x into Z, which means you have to get rid of it in an extra step.

Instead of LASTxy, I'd prefer an UNDO recalling the entire stack as it was before that erroneous last operation. KISS (but it has to be determined whether that's viable with the WP 34S).

Just my 20m€.
d:-)

My intuitive suggestion for CPX RCL L was Z->T, Y->Z, X->thin air, LastY->Y LastX->X. X can be discarded, because its result was never intended.
UNDO of the entire stack would be much more attractive, because it includes also complex dyadic functions (but it has to be determined ......).

Bernhard