# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 600, 400 
# set output 'pm3dcolors.8.png'
set format cb "%3.1f" 
unset key
set view map scale 1
set samples 101, 101
set isosamples 2, 2
set style function pm3d
set xtics  norangelimit 2 
unset ytics
unset ztics
set cbtics  norangelimit 0.1 
set title "set palette model RGB defined\n(0 'green', 1 'dark-green', 1 'yellow', 2 'dark-yellow', 2 'red', 3 'dark-red' )" 
set trange [ * : * ] noreverse nowriteback
set urange [ * : * ] noreverse nowriteback
set vrange [ * : * ] noreverse nowriteback
set xrange [ -10.0000 : 10.0000 ] noreverse nowriteback
set x2range [ * : * ] noreverse writeback
set yrange [ * : * ] noreverse writeback
set y2range [ * : * ] noreverse writeback
set zrange [ * : * ] noreverse writeback
set cbrange [ 0.00000 : 1.00000 ] noreverse nowriteback
set rrange [ * : * ] noreverse writeback
set palette defined ( 0 0 1 0, 0.3333 0 0.3922 0, 0.3333 1 1 0,\
     0.6667 0.7843 0.7843 0, 0.6667 1 0 0, 1 0.5451 0 0 )
set colorbox vertical origin screen 0.9, 0.2 size screen 0.05, 0.6 front  noinvert bdefault
g(x)=x
f(x)=(x+10)/20
NO_ANIMATION = 1
splot f(x)