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gnuplot

How to plot several datasets with titles from one file in Gnuplot?

Assuming I have a file that looks like this (note the double newlines):

"p = 0.1"
1 1
3 3
4 1


"p = 0.2"
1 3
2 2
5 2

Is it possible to make Gnuplot plot these two datasets in one plot with the titles given on the first line of each dataset?

Solution

  • It's definitely possible and your datafile is already the correct format. The functionality you're looking for is built into columnheader(N) which reads the data at the top of the N'th column and uses it as the plot title:

     plot 'test.dat' i 0 u 1:2 w lines title columnheader(1),\
      'test.dat' i 1 u 1:2 w lines title columnheader(1)

    which can be condensed using iteration:

    plot for [IDX=0:1] 'test.dat' i IDX u 1:2 w lines title columnheader(1)