Gyroid slab from equation

A slab of pure gyroid

I was fascinated by the gyroid shape elsewhere in thingiverse. I do not have the software tools to make gyroid models the same way, but I discovered that I could do it with the open source program Octave.

The basic equation is

(sin(x*k).*cos(y*k)+sin(y*k).*cos(z*k)+sin(z*k).*cos(x*k)) == 0

It takes a little more than that to get a proper stl files that is a closed surface with a thickness, of course. See the comments in "gyroid_slab_2.m" for more details.