# set terminal png transparent nocrop enhanced font arial 8 size 420,320 
# set output 'param.2.png'
set dummy t,y
set key right below Right noreverse noinvert enhanced box linetype -1 linewidth 1.000 samplen 4 spacing 1 width 0 height 0 autotitles
set parametric
set samples 160, 160
plot sin(t)/t,t