# set terminal pngcairo  background "#ffffff" enhanced font "arial,10" fontscale 1.0 size 600, 400 
# set output 'heatmaps.3.png'
unset key
set view map
set style data lines
set xtics border in scale 0,0 mirror norotate  offset character 0, 0, 0 autojustify
set ytics border in scale 0,0 mirror norotate  offset character 0, 0, 0 autojustify
set ztics border in scale 0,0 nomirror norotate  offset character 0, 0, 0 autojustify
set nocbtics
set rtics axis in scale 0,0 nomirror norotate  offset character 0, 0, 0 autojustify
set title "Heat map with non-zero pixel values written as labels" 
set xrange [ -0.500000 : 4.50000 ] noreverse nowriteback
set yrange [ -0.500000 : 4.50000 ] noreverse nowriteback
set cblabel "Score" 
set cbrange [ 0.00000 : 5.00000 ] noreverse nowriteback
set palette rgbformulae -7, 2, -7
x = 0.0
plot $map1 matrix using 1:2:3 with image,      $map1 matrix using 1:2:($3 == 0 ? "" : sprintf("%g",$3) ) with labels