main.pgf-plot.gnuplot

set table "main.pgf-plot.table"; set format "%.5f"
set format "%.7e";; set parametric; set pm3d explicit; set pal rgb 9,9,3; set hidden3d; set isosamples 18,48; set xrange[-8:10]; set yrange[-9:9]; set urange[0:2*pi]; set vrange[0:4*pi]; x(u,v)= v<pi ? (2.5-1.5*cos(v))*cos(u): v<2*pi ? (2.5-1.5*cos(v))*cos(u): v<3*pi ? -2+(2+cos(u))*cos(v): -2+2*cos(v)-cos(u); y(u,v)= v<pi ? (2.5-1.5*cos(v))*sin(u): v<2*pi ? (2.5-1.5*cos(v))*sin(u): v<3*pi ? sin(u): sin(u); z(u,v)= v<pi ? -2.5*sin(v): v < 2*pi ? 3*v-3*pi: v<3*pi ? (2+cos(u))*sin(v)+3*pi: -3*v+12*pi; set multiplot; splot x(u,v),y(u,v),-z(u,v) w pm3d; splot x(u,v),y(u,v),-z(u,v) lt 4; unset multiplot;