pltファイルの例(gnuplot.plt)
set terminal postscript eps enhanced color solid 20
set size 0.78, 1
set view 0, 0
set key outside
set xrange [0:50]
set yrange [0:50]
set cbrange [0:1]
set xlabel ""
set ylabel ""
set zlabel ""
set xtics 0
set ytics 0
set ztics 1
set cbtics 0.2
set format z ""
set ticslevel 0
set isosamples 50, 50
set palette defined (0 "blue", 1 "red")
set output "gnuplot.eps"
splot "Data.dat" index 0 u 1:2:3 w pm3d lt 1 notitle