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set samples 1000
set title "[][][]"
set ylabel "[][][]"
set terminal postscript
set output "xxx.ps"

set key outside
set key bottom outside
set key below
set xrange [0:10]
set y2tics
set y2label "[][][]"
plot "[][]1.dat", "[][]2.dat" axes x1y2 title "[][]"

set terminal postscript plus
set size 1.0, 0.5
set rmargin 15
set multiplot
set origin 0, 0.5
set title "(1)"
plot "[][]1.dat" title "$\\theta$"
set origin 0, 0
set title "(2)"
plot 3.14159/2*cos(x) title "$( \\pi /2) \\cos t$"