Differences between graphics_toolkits, greek letters

[Walter White]

Hello,

I have some questions about the different graphics toolkits available in Octave
and hope that you can help me as I could not find any documentation on this topic.
(Octave 3.4.3, Windows 7)

Which toolkit is recommended to date? Where are the main differences?
Is the support for gnuplot being dropped in the future?

Which toolkit provides more possibilities, in my case primary related to printing figures to
files, but also other common possibilities?

I ran the script attached below to examine the labelling of plots by gnuplot and fltk
and fltk does not print any greek letters. Is it possible?

Gnuplot does not support greek letters in the legend, do you know a
way to achieve this?

Kind regards,
Walter

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x = 1:10
y = rand(10,1)

label_string = '\eta_{efficiency} \epsilon^{2} \lambda \lambda \circ \alpha'

graphics_toolkit('gnuplot')
legend = sprintf('r-;%s;',label_string);
plot(x,y,legend)

ylabel(label_string)
xlabel(label_string)
title(label_string)
print_filename = sprintf('./test_gnuplot.png')
print(print_filename, '-dpng','-FHelvetica:8','-S1024,768')
close all

graphics_toolkit('fltk')

legend = sprintf('r-;%s;',label_string);
plot(x,y,legend)

ylabel(label_string)
xlabel(label_string)
title(label_string)
print_filename = sprintf('./test_fltk.png')
print(print_filename, '-dpng','-FHelvetica:8','-S1024,768')
close all
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