[Octave-bug-tracker] [bug #51772] Errors when running compare_plot_demos with gnuplot toolkit on Windows

[Dan Sebald]

Follow-up Comment #2, bug #51772 (project octave):

The error messages are coming from gnuplot, not Octave.

Demos 5 and 6 work on my linux system, but it's clear what the problem is.  It
looks like your example is failing with the interactive terminal plot (prior
to attempting a PNG file).  Attached is the screenshot of my interactive
terminal.  Notice how small the plot region is because of how large of space
is left in the margins.  The resulting PNG looks similar.

I would guess on your system the margins are so big, relatively speaking, that
there is few if any pixels left for the actual plot.  gnuplot then gives the
error message you see and must get in a bad state as far as some intermediate
data file.  The fact that gnuplot can't do follow-up plots after that
condition may be a gnuplot bug which I will investigate.

The main issue with Octave, though, is that the demo 5 is using space much too
big in the margins.  I'm also attaching the gnuplot commands that Octave
generates, i.e.,


drawnow ("qt", "/dev/null", "a5_demo.gp");


and the size of the plot is set within with


unset tmargin;
unset bmargin;
unset lmargin;
unset rmargin;
set origin 0, 0.3667;
set size ratio -1 1, 0.2666;


So the Octave scripts for the gnuplot toolkit are choosing far too big margins
for some reason.

(file #41556)
    _______________________________________________________

Additional Item Attachment:

File name: axis_demo5_Screenshot_from_2017-08-17_11:49:18.png Size:20 KB


    _______________________________________________________

Reply to this item at:

  <http://savannah.gnu.org/bugs/?51772>

_______________________________________________
  Message sent via/by Savannah
  http://savannah.gnu.org/