On my Ubuntu, Gnuplot plots into a Qt window (terminal type
qt) by default. Every invocation of the
plot command redraws the contents of this single Qt window.
Sometimes, I need to plot two different data sets in two different windows, so that I can compare them side-by-side. To do this specify a window number, an integer starting from
set terminal qt 0 plot("data_0.txt") set terminal qt 1 plot("data_1.txt")
Tried with: Gnuplot 5.0 and Ubuntu 14.04