Loop structure inside gnuplot?

Solution 1:

There sure is (in gnuplot 4.4+):

plot for [i=1:1000] 'data'.i.'.txt' using 1:2 title 'Flow '.i

The variable i can be interpreted as a variable or a string, so you could do something like

plot for [i=1:1000] 'data'.i.'.txt' using 1:($2+i) title 'Flow '.i

if you want to have lines offset from each other.

Type help iteration at the gnuplot command line for more info.

Also be sure to see @DarioP's answer about the do for syntax; that gives you something closer to a traditional for loop.

Take a look also to the do { ... } command since gnuplot 4.6 as it is very powerful:

do for [t=0:50] {
  outfile = sprintf('animation/bessel%03.0f.png',t)
  set output outfile
  splot u*sin(v),u*cos(v),bessel(u,t/50.0) w pm3d ls 1
}

http://www.gnuplotting.org/gnuplot-4-6-do/

I have the script all.p

set ...
...
list=system('ls -1B *.dat')
plot for [file in list] file w l u 1:2 t file

Here the two last rows are literal, not heuristic. Then i run

$ gnuplot -p all.p

Change *.dat to the file type you have, or add file types.

Next step: Add to ~/.bashrc this line

alias p='gnuplot -p ~/./all.p'

and put your file all.p int your home directory and voila. You can plot all files in any directory by typing p and enter.

EDIT I changed the command, because it didn't work. Previously it contained list(i)=word(system(ls -1B *.dat),i).