files = system('ls data/output_re_optical_depth_*.res') samplefile = system("ls data/output_re_optical_depth_*.res | head -1| awk '{print $NF}'") param = system('head -n 1 ' . samplefile . ' | cut -d "#" -f 2 | cut -d "=" -f 1') set title param set xlabel 'l' set ylabel 'D_{l}' set xrange [0:2500] set yrange [0:] plot for [file in files] file u 1:2 title system("head -n 1 ".file." | cut -d '#' -f 2") w l