Re: Octave scripts and GnuPlot

[Rob Mahurin]

On Mar 23, 2009, at 7:23 AM, Olaf Pohlmann wrote:
> If I call this from the interactive shell with source('moebius.m'),
> GnuPlot stays open. Apparently the shell forks another process, since
> it isn't blocked while GnuPlot is open. Is there a way to get the same
> behavior in a script?

octave --persist will give you a command prompt after running your  
script.
Calling
        gnuplot_binary("gnuplot -persist")
will keep gnuplot's x11 output on screen after gnuplot exits.

> And on the other hand: if I only want to create
> an image file, is there a way to prevent GnuPlot from being launched?

set(gcf,"visible","off") before plotting.

> [...] I don't really understand what triggers the
> launch of GnuPlot, I thought is was the call of the axis command.

I think the plot commands go into some queue, which is emptied into  
gnuplot when an interactive prompt returns.  The idea being that  
piping to gnuplot is expensive, and so a script like

        plot();
        xlabel("this");
        ylabel("that");
        set(gca,"something")

should only call gnuplot once.  If I'm wrong a real expert will pipe up.

Cheers,
Rob

--
Rob Mahurin
Department of Physics and Astronomy
University of Tennessee                 865 207 2594
Knoxville, TN 37996                     address@hidden