set terminal png transparent
set   autoscale                        # scale axes automatically
unset log                              # remove any log-scaling
unset label                            # remove any previous labels
set xtic auto                          # set xtics automatically
set ytic auto                          # set ytics automatically
set output 'Q1.png'
set title "//movie/actor"
set xlabel "XML input file size (Kb)"
set ylabel "Execution time (seg)"
set key  left box
plot  "Q1.dat" using 1:2 title 'Lazy' with linespoints,\
"Q1.dat" using 1:3 title 'Not Lazy' with linespoints,\
"Q1.dat" using 1:4 title 'Saxon' with linespoints,\
"Q1.dat" using 1:5 title 'Saxon Compiled' with linespoints