# set terminal pngcairo  transparent enhanced font "arial,10" fontscale 1.0 size 600, 400 
# set output 'pm3dcolors.9.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 file \"-\" (file with 3 columns)" 
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 0 0, 0.25 0 0 1, 0.5 0 1 0,\
     0.75 1 0 0, 1 1 1 1 )
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
## Last datafile plotted: "-"
splot f(x)