plot **** lw 2
plot **** lc rgb "red"
gnuplot> set logscale
gnuplot> set xrange[1:3]
gnuplot> plot "data1.dat" using 1:2 notitle with lines,\
gnuplot> "data2.dat" usi 1:3 ti "凡例1" w lines
gnuplot> set xlabel "x"
gnuplot> set ylabel "y"
gnuplot> set title "タイトル"
gnuplot> replot
gnuplot> set xtics 2
gnuplot> set format y "10^{%g"}
gnuplot> set terminal postscript eps enhanced
set size square