I like gnuplot – it’s great for a quick visualisation of some data or for scripting a large number of quick and dirty plots. I suspect that I’m not alone in that (a) I wish that I had more facility with it and (b) partly because of (a), I tend towards more pointy-clicky tools such as OpenOffice for publication-quality plots.
Anyway, this site has some great gnuplot tips. My favourite – how do you label data points using gnuplot? You require a separate file of labels (which I’d say was con not a pro), but a Perl one-liner can easily do this for you. Assuming that your data matrix, “data.dat” looks like this:
A B C D
a 1 2 3 4
b 5 6 7 8
c 1 2 3 4
d 5 6 7 8
and you want to plot columns 2:3 – that is (1,2), (5,6) and so on, using column 1 (a, b, c, d) as labels then:
perl -ane ‘print “set label \”$F[0]\” at $F[1],$F[2]\n”‘ data.dat > label.plt
does the trick. Edit out the first line of label.plt, then in gnuplot:
load “label.plt”
plot “data.dat” using 2:3
This will centre the data labels on each point so you may need to fiddle with the exact positioning.
