gnuplot-info

[Gnuplot-info] A question about Gnuplot 4.0 on Unix

[Timo L. <la...@it...>]

Hello,

If I have two datafiles, let's say "foo1.dat" and "foo2.dat", and I 
want to plot the difference between these two files in gnuplot, for 
example, I might want to plot column 2 in "foo2.dat" minus column 2 
in "foo1.dat", how do I achieve this in gnuplot 4.0 ?

I'm sorry if this is already written down somewhere in the helpfile or 
the demos, but I can't seem to find anything relevant to this 
question.

Any help would be appreciated,

Regards,

	Timo

Re: [Gnuplot-info] A question about Gnuplot 4.0 on Unix

[<br...@ph...>]

Timo Lahde wrote:

> If I have two datafiles, let's say "foo1.dat" and "foo2.dat", and I 
> want to plot the difference between these two files in gnuplot, for 
> example, I might want to plot column 2 in "foo2.dat" minus column 2 
> in "foo1.dat", how do I achieve this in gnuplot 4.0 ?

By combining the data into a single file outside gnuplot, before or 
while plotting them.  On a Unix-ish box, something like this would work:

	plot "< paste foo1.dat foo2.dat" u 1:($4-$2)

See "help datafile special"