How to make x axis lie on y=0 on Octave gnuplot?

Question

How to make x axis lie on y=0? Right now it's lying on whatever is ymin.

Answer 1

I do not know if they changed syntax in Octave versions or there is something specific in my code or functions but with Octave version 4.4.1 I was not able to get this axis with "zero" but with "origin"

    set (gca, "xaxislocation", "origin")

Answer 2

You can add zeroaxis with the set command:

plot(...)
set(gca, "xaxislocation", "zero")

You may also want to add:

set(gca, "box", "off")

There is a similar discussion on the octave mailinglist.