# set terminal pngcairo transparent enhanced font "arial,10" fontscale 1.0 size 500, 350 # set output 'pm3d.9.png' set border 4095 front linetype -1 linewidth 1.000 set view map set samples 50, 50 set isosamples 50, 50 unset surface set style data pm3d set style function pm3d set ticslevel 0 set title "colour, rgbformulae 3,11,6 ... green-red-violet" 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 b set palette rgbformulae 3, 11, 6 splot sin(sqrt(x**2+y**2))/sqrt(x**2+y**2)