Cursor Mode; The Cas Home History - HP 39g Master Manual

If you want to delete the entire expression then the simplest method is to
press ON and exit the CAS and then re-enter it with a blank screen.
Alternatively you can highlight part or all of the expression and then press
SHIFT ALPHA CLEAR. The highlighted section will be cleared.
Cutting and pasting of all or part of an
expression can be easily done using the
menu. This provides access to
commands of Cut, Copy and Paste which
behave in exactly the same manner as they do
in any word processor.
Simply highlight the relevant portion of the expression first and then either cut
or copy it. Then move to the new position and paste it. As you can imagine
from the tree structure the results of a paste can sometimes be unexpected
but generally they will be satisfactory.

Cursor mode

Cursor mode can be used to select portions of
an expression by drawing a box around it.
From the menu, select 'Cursor mode'.
Use the arrow keys to move a cursor around
on the screen. As you do so it places a box
around different parts of the expression that
are selectable. Press ENTER to select that section.

The CAS HOME History

The CAS has its own history which is
essentially similar in its behavior to the normal
HOME History. If you press HOME while in the
CAS then you will see something similar to the
view on the right, with all previous calculations
and results recorded. As with the normal
History it is worth deleting the contents regularly by pressing if the
memory is not to be gradually used up.
To re-use an expression just highlight it and press . Pressing
will copy the expression to the clipboard so that you can then Paste it using
the menu. Pressing will present the expression in scrollable
form.
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