Thank you Henrique for showing me how to use --matrix= as an option for gnuplot. I simply missed this option in the manual. Now I think I have something not in the manual: Can I plot 2 sets of X-Y variables in a single gnuplot with one showing a connected line and the other x points ? The problem is the 2 sets have different matrix lengths (rows) The following gnuplot input gives the basic look but I have about 10,000 more scatter points to plot # set term pngcairo font "verdana,8" set encoding utf8 set style line 1 lc rgb "#ff0000" lw 2 set style line 2 lc rgb "#ff0000" set xzeroaxis set title "Mean-Variance Efficient Frontier" set ylabel "Expected return" set xlabel "Std-dev" set grid ytics set yrange [0:8] set xrange [0:100] plot \ '-' using 1:($2) title "" w lines, '-' using 1:($2) title "" w points 37.34392177 2.97360052 38.93497674 3.315788614 41.15302283 3.657976708 43.90313334 4.000164802 47.09218512 4.342352895 50.63731467 4.684540989 54.46904008 5.026729083 58.5311026 5.368917177 62.7788067 5.71110527 e 47.87386803 4.236153823 53.21768427 4.637368399 48.34658154 4.233955778 52.43479596 4.640319946 51.23960034 4.49318912 63.37821207 5.368805231 51.19436633 4.531811607 55.52425526 4.746143464 57.27659417 4.984767162 50.46428986 4.468835106 52.99520784 4.614860001 52.77690827 4.707596727 47.30102507 4.201675871 50.27836542 4.500478414 e I could live with gnuplot 1 2 --matrix=A --input="@fname" --output=display with a file holding the line values, but I could not seem to combine --matrix & --input and it seems you can not add the line using plot commands enclosed in { } either. Am I right about this?