#260 gnuplot is not working while plotting 6GB file size

[Sagar Kashid]

I am able to plot 120MB file with gnuplot, but unable to do the same when file size becomes 6GB
getting following error while doing the same

gnuplot> p 'step.000010.dat' w l
gnuplot> Qt has caught an exception thrown from an event handler. Throwing
exceptions from an event handler is not supported in Qt. You must
reimplement QApplication::notify() and catch all exceptions there.
terminate called after throwing an instance of 'std::bad_alloc'
what(): std::bad_alloc
Error: plot window (gnuplot_qt) not responding - will restart

Let me know if there is any solution for this

[Ethan Merritt]

I doubt that the error is due to the file size per se. The error message is coming from Qt, which means the data has already been read from the file and the resulting plot is being sent to the Qt terminal. Of course if the input file is huge it may also be generating a huge number of lines in the plot; I would guess that the number of plotted lines is too large for some Qt buffer. The easiest way to confirm this would be to set the output to something other than Qt, preferably to a terminal that streams the output rather than accumulating it in a buffer. I suggest testing with

      set term postscript color
      set output 'big_plot.ps'
       p 'step.000010.dat' w l

I predict you will get a very large postscript output file but no error from the program. If that's not what happens, please report back with the new error message. You could also report what, if anything, was written successfully to the postscript file before this new failure.

If the problem is indeed too many lines in the plot, stop and think about whether it makes sense to plot all those lines. Surely that is too many to distinguish! I don't know what sort of lines these are, but you might try plotting, say, every 100th input line or maybe every 10000th for a truly immense input file.

       p 'step.000010.dat' every 100 w l

[Sagar Kashid]

Thank you so much for your reply, I was using same commands for work around.
do you think i have to check with QT as earlier i could able to generate/display the same plot, but recently getting this type of error

[Sagar Kashid]

Thank you Ethan for your help, issue was due to QT only. I could able to plot if set terminal is x11
you may close the issue