HP 39gs Master Manual page 266

The final option is 'Show function'. The program this runs is a little more complex than the ones shown so far
and illustrates a useful technique.
The line:
'((X+2)^3+4)/(X-2)'
stores the expression
Notice the way the function is in single quotes so that the algebraic expression itself is used rather than its
value when evaluated using the current contents of memory X. If you wanted to graph this function by setting
the post execution view number to 1 (the
in order to it or it would not graph. You may wish to edit the
1:
try this.
The next lines display the expression using the four options available.
The line:
GROB G1;F1(QUOTE(X));0:
converts the expression
each repetition, controls the font used to display the function.
The line:
DISPLAY G1:
displays this GROB on the screen, and then
F1(X):
( )
3
x + 2 + 4
into the function
( )
x − 2
PLOT
into a Graphic Object (GROB). The number at the end, which changes with
F1(X)
FREEZE
.
F1(X)
view), then you would need to include the command
freezes the display until a key is pressed.
266
and
.MSG.SV .MSG.FN
CHECK
program to