Finding local max points

Hello!

I am quite new to grasshopper so this might have an easy answer.

I have made a surface and curved it with points referenced from rhino in a way that makes these edges. Is there a way to find the "tips" where three edges meet? 

Thank you in advance!

Edit: I will clarify what the surface are made from. A base grid of points are lied out in xyplane. The points in the grid have a distance to several manually added points. The distance to the closest point is the displacement i z for said point in the grid. This displacement of all points in the base grid is the surface we see here.