set key graph 0.4,0.95 set label "3F" at graph 0.02,0.95 set xlabel "objective functions" set ylabel "time (seconds)" set terminal fig big thickness 1 fontsize 18 set pointsize 1 plot "trial3F.plt" index 0 t "version-4" with linespoints pointtype 5 replot "trial3F.plt" index 1 t "version-3" with linespoints pointtype 1 set output "trial3F.fig" replot