A graph needs printed axes, so you can orient yourself. For a do-once project, it may be reasonable to draw the axes by hand using Emacs’s Picture mode; but a graph drawing function may be used more than once.
For this reason, I have written enhancements to the basic
print-graph-body function that automatically print labels for
the horizontal and vertical axes. Since the label printing functions
do not contain much new material, I have placed their description in
an appendix. See A Graph with Labeled Axes.