reset
set terminal postscript eps enhanced color font "Helvetica" 24
set output "fig_gpl_torus.eps"
set size ratio 1.0

set xtics -6,2,6
set ytics -6,2,6
set ztics -2,2,2
set parametric
set urange[0:2*pi]
set vrange[0:2*pi]
set ticslevel 1.0
set isosamples 45,45
set hidden3d
#set view 15,30
a=2
b=4
splot b*cos(u)+a*cos(v)*cos(u),b*sin(u)+a*cos(v)*sin(u),a*sin(v) notitle