# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 500, 350 
# set output 'pm3d.5.png'
set border 4095 front linetype -1 linewidth 1.000
set view 50, 50, 1, 1
set samples 25, 25
set isosamples 20, 20
unset surface
set ticslevel 0
set title "set pm3d at bstbst (funny combination, only for screen or postscript)" 
set xlabel "x" 
set xrange [ -15.0000 : 15.0000 ] noreverse nowriteback
set ylabel "y" 
set yrange [ -15.0000 : 15.0000 ] noreverse nowriteback
set zrange [ -0.250000 : 1.00000 ] noreverse nowriteback
set pm3d implicit at bstbst
splot sin(sqrt(x**2+y**2))/sqrt(x**2+y**2)