Anchor some of the naked edges

Hi, I’m a beginner. I know how to make a simple tensile structure, with for instance corner points or edges anchored. I’m trying to anchor only some of the edges, for instance those with x=n, or only the horizontal ones. I’ve tried using dispatch but cannot get these edges asca submit…

Any clue? Or any tutorial I should follow?

Thanks!

If you want any help please share your grasshopper definition with internalised inputs…