# This is a comment line
# One can can cut and paste this file into gnuplot
# You can do a line at a time or groups of lines up to a plot or splot
#
# Basic plot of the saddle surface
splot x**2 - y**2
# 
# the default plot is -10 <= x <= 10 and -10 <= y <= 10
#
set xrange [-3:3]
set yrange [-3:3]
splot x**2 - y**2
# note that changing the range didn't change the shape (the z-axis 
# auto scales). One can limited the z range by
set zrange [-6:6]
splot x**2 - y**2
# and return to the default by
set zrange [*:*]