HP HP-25 - HP-25 Function Key Guide; LAST X Register Functionality

Section 4
Function Keys
The HP-25 function keys can be used manually or keyed in as
part
of
a
program.
In
this
section,
each
key
is
individually
ex-
plained. To use function keys manually, ensure that the
PRGM-RUN switch erem [T ruv is set to RUN.
LAST X
In addition to the four stack registers that automatically store
intermediate results, the HP-25 also contains a separate auto-
matic register, the LAST X register. This register preserves
the value that was in the displayed X-register before the per-
formance of a function. To place the contents of the LAST X
register into the display again, press| 7 [Cior .
Recovering from Mistakes
makes it easy to recover from keystroke mistakes,
such as pressing the wrong function key or keying in the wrong
number.
Example: Divide 12 by 2.157 after you have mistakenly divided
by 3.157.
Press Display
2
3.157(F Oops! You made a mistake.
Retrieves that last entry.
You're back at the beginning.
2.157 5] The correct answer.
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