Undo and cmd functions, Undo and cmd functions ,2-62 – HP 50g Graphing Calculator User Manual

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variable p1. Press I

@PURGE@ J@@p1@@ `. The screen will now show

variable p1 removed:

You can use the PURGE command to erase more than one variable by placing
their names in a list in the argument of PURGE. For example, if now we wanted
to purge variables R and Q, simultaneously, we can try the following exercise.
Press :

@PURGE@ „ä³ J@@@R!@@ ™ ‚í ³ J@@@Q!@@

At this point, the screen will show the following command ready to be executed:

To finish deleting the variables, press `. The screen will now show the
remaining variables:

Using function PURGE in the stack in RPN mode
We start again at subdirectory {HOME MANS INTRO} containing variables
p1, z1, Q, R, and

. We will use command PURGE to delete variable p1.

Press ³

@@p1@@ ` I @PURGE@. The screen will now show variable p1

removed:

To delete two variables simultaneously, say variables R and Q, first create a list
(in RPN mode, the elements of the list need not be separated by commas as in
Algebraic mode): J „ä³

@@@R!@@ ™ ³ @@@Q!@@ `. Then, press

@PURGE@ use to purge the variables.

UNDO and CMD functions

Functions UNDO and CMD are useful for recovering recent commands, or to
revert an operation if a mistake was made. These functions are associated with