# set terminal svg size 600,400 dynamic enhanced font 'arial,10' mousing name "imageNaN_8" butt dashlength 1.0 
# set output 'imageNaN.8.svg'
unset key
set label 1 "NaN\nshould appear as\nbackground" at 3.00000, 2.00000, 0.00000 center norotate front nopoint
set label 2 "Negative values become NaN\nwith a log-scale color mapping" at 0.00000, 2.50000, 0.00000 left norotate back nopoint
unset xtics
unset ytics
set cbtics  norangelimit logscale autofreq 
set title "negative values mapped to log-scale colorbar" 
set xrange [ * : * ] noreverse writeback
set x2range [ * : * ] noreverse writeback
set yrange [ * : * ] noreverse writeback
set y2range [ * : * ] noreverse writeback
set zrange [ * : * ] noreverse writeback
set cbrange [ 0.100000 : 10.0000 ] noreverse writeback
set rrange [ * : * ] noreverse writeback
set logscale cb 10
NO_ANIMATION = 1
## Last datafile plotted: "$DATA"
plot $DATA with image, $DATA using 1:2:(sprintf("%g",$3)) with labels tc rgb "green"