# set terminal svg size 600,400 dynamic enhanced font 'arial,10' mousing name "discrete_3" butt dashlength 1.0 
# set output 'discrete.3.svg'
set contour base
set cntrparam levels 6
set cntrparam levels incremental -20,5
set style data lines
set title "incremental contours starting at -20, stepping by 5" 
NO_ANIMATION = 1
splot x*y